Assessing analgesia in single and repeated administrations of propacetamol for postoperative pain: comparison with morphine after dental surgery. Intravenous acetaminophen (paracetamol): comparable analgesic efficacy, but better local safety than its prodrug, propacetamol, for postoperative pain after third molar surgery. Analgesic efficacy and safety of intravenous paracetamol (acetaminophen) administered as a 2 g starting dose following third molar surgery. Clinical equivalence of IV paracetamol compared to IV dipyrone for postoperative analgesia after surgery for breast cancer. [Analgesic and opioid-sparing effects of intravenous paracetamol in the early period after aortocoronary bypass surgery]. [Comparison of propacetamol and morphine in postoperative analgesia]. Analgesic effect of i.v. paracetamol: possible ceiling effect of paracetamol in postoperative pain. Analgesic efficacy of parenteral paracetamol (propacetamol) and diclofenac in post-operative orthopaedic pain. Paracetamol versus metamizol in the treatment of postoperative pain after breast surgery: a randomized, controlled trial. Propacetamol as adjunctive treatment for postoperative pain after cardiac surgery. Efficacy and safety of single and repeated administration of 1 gram intravenous acetaminophen injection (paracetamol) for pain management after major orthopedic surgery. A comparison between IV paracetamol and IV metamizol for postoperative analgesia after retinal surgery. Intravenous paracetamol improves the quality of postoperative analgesia but does not decrease narcotic requirements. The morphine-sparing effect of propacetamol in orthopedic postoperative pain. Effect of paracetamol and coxib with or without dexamethasone after laparoscopic cholecystectomy. Postoperative analgesia with i.v. propacetamol and ketoprofen combination after disc surgery. Lack of pre-emptive analgesic effect of (R)-ketamine in laparoscopic cholecystectomy. Diclofenac and/or propacetamol for postoperative pain management after cesarean delivery in patients receiving patient controlled analgesia morphine. Intravenous tramadol compared to propacetamol for postoperative analgesia following thyroidectomy. Efficacy of propacetamol in the treatment of postoperative pain. Morphine-sparing effect in orthopedic surgery. Italian Collaborative Group on Propacetamol. [A randomized, double blind, and controlled clinical trial of the non-addictive propacetamol in postoperative analgesia]. [Patient-controlled postoperative analgesia in orthopedic surgery: epidural PCA versus intravenous PCA]. Propacetamol versus ketorolac for treatment of acute postoperative pain after total hip or knee replacement. Onset of acetaminophen analgesia: comparison of oral and intravenous routes after third molar surgery. Additive analgesic effect of codeine and paracetamol can be detected in strong, but not moderate, pain after Caesarean section. Baseline pain-intensity is a determinant of assay-sensitivity in a postoperative analgesic trial. Propacetamol and diclofenac alone and in combination for analgesia after elective tonsillectomy. No effect of preoperative paracetamol and codeine suppositories for pain after termination of pregnancies in general anaesthesia. Multimodal analgesia before thoracic surgery does not reduce postoperative pain. The effect of paracetamol or diclofenac administered before operation on postoperative pain and behaviour after adenoidectomy in small children. Comparison of parecoxib and proparacetamol in endoscopic nasal surgery patients. [The efficacy of paracetamol (Tylenol) and acetyl salicylic acid (Aspirin) in treating postoperative pain].
We conducted this double-blinded, randomized study to assess the analgesic effect of repeated administrations of paracetamol, administered as propacetamol, an injectable prodrug formulation of paracetamol, and to compare this with the analgesic effects of morphine. Patients experiencing moderate to severe pain after elective surgical removal of bone-impacted third-molar teeth under general anesthesia were randomly assigned to receive IV propacetamol 2 g (n = 31), IM morphine 10 mg (n = 30), or placebo (n = 34). Five hours later, the treatments were readministered at half of the previous dosages. Standard measures of analgesia were collected repeatedly for 10 h. Propacetamol and morphine were significantly more effective than placebo in all primary measures of analgesia over 5 h after the first administration and globally over 10 h (first and second administrations). After the first dose, 21 of the 34 patients in the placebo group required rescue medication, compared with 6 of the 31 in the propacetamol group (P < 0.0009) and 4 of the 30 in the morphine group (P < 0.0001). No statistically or clinically significant differences were found between propacetamol and morphine for any sum or peak measures of analgesia. No serious adverse events were reported; adverse events were significantly less frequent in the propacetamol group than in the morphine group (P < 0.027). Propacetamol administered IV in repeated doses (2 g followed by 1 g) has a significant analgesic effect that is indistinguishable from that of morphine administered IM (10 mg followed by 5 mg) after dental surgery, with better tolerability.
                After moderately painful surgical procedures, IV paracetamol, administered as propacetamol, may be an asset in the control of acute postoperative pain. We compared an acetaminophen (paracetamol) 1 g (n = 51) formulation for infusion with propacetamol 2 g (n = 51) and placebo (n = 50) in a randomized, controlled, double-blind, parallel group trial in patients with moderate-to-severe pain after third molar surgery. Treatment efficacy was assessed in house for 6 h after starting the 15-min infusion. Significant effects versus placebo (P < 0.01) were obtained with both active treatments on pain relief, pain intensity difference on a 100-mm visual analog scale, and on a categorical scale (except for propacetamol at 6 h). No significant differences were noted between active groups except at 1 h. Six-hour weighted sums of primary assessments showed significantly better efficacy than placebo (P < 0.0001) and no difference between active treatments. Median stopwatch time to onset of pain relief for active treatment was 6-8 min after infusion start. Active treatments showed comparable efficacy with a significantly longer duration of analgesia and better patients' global evaluation compared with placebo. The incidence of patients reporting local pain at the infusion site was significantly less frequent after IV acetaminophen or placebo (0%) in comparison with propacetamol (49%). In conclusion, acetaminophen 1 g and propacetamol 2 g were superior to placebo regarding analgesic efficacy, with a more frequent incidence of local pain at the infusion site for propacetamol. The recommended dose for intravenous (IV) paracetamol injection in adults is 1g, however pharmacokinetic and pharmacodynamic findings suggest that a better analgesia could be obtained with a 2 g starting dose.
                A single-centre, randomised, double-blind, placebo-controlled, 3-parallel group study was performed to demonstrate the analgesic efficacy and safety of IV paracetamol 2 g. Following third molar surgery, patients reporting moderate to severe pain received a single 15-min infusion of either IV paracetamol 2 g, IV paracetamol 1g or placebo. Efficacy and safety were evaluated over 8 h. Laboratory tests were performed before and 48 h after drug administration.
                Two hundred and ninety seven patients (132 = IV paracetamol 2g; 132 = IV paracetamol 1g; 33 = placebo) were randomised and completed the study. The summed pain relief over 6h (TOTPAR6) was significantly superior with IV paracetamol 2 g as compared to IV paracetamol 1g and placebo (p < 0.0001). Pain relief scores of IV paracetamol 2g were significantly superior to IV paracetamol 1g and to placebo from T30' to T8h (p < 0.0001). Median duration of analgesia was significantly longer following IV paracetamol 2 g compared to IV paracetamol 1g and placebo (p < 0.0001). Adverse events occurred with the same frequency in the 3 treatment groups. No clinically significant changes from baseline were observed for vital signs or laboratory tests.
                The analgesic efficacy of a 2 g starting dose of IV paracetamol was superior over the recommended dose of 1g in terms of magnitude and duration of analgesic effect for postoperative pain following third molar surgery, with no significant difference between groups regarding safety. To assess clinical efficacy of IV paracetamol 1 g and IV dipyrone 1 g on a 24-h dosing schedule in this randomised, double-blinded study of 40 ASA I-III (American Society of Anesthesiologists classification of physical status) patients undergoing surgery for breast cancer.
                General anaesthesia using remifentanil and propofol was performed for surgery. The patients were randomly allocated to two groups, receiving infusions of paracetamol 1 g/100 mL (Para Group) or of dipyrone 1 g/100 mL (Dipy Group) 30 min before arrival in the recovery area and every 6 h up to 24 h postoperatively. All patients had unrestricted access to opioid rescue medication via an IV patient-controlled analgesia (PCA) device.
                The primary variables for clinical equivalence were the differences between the mean values for pain scores at rest and pain scores on coughing over 30 h postoperatively. The equivalence margin was determined as +/-10 mm on the visual analogue scale (VAS).
                Regarding pain scores at rest, the 90% CI of the mean differences between the treatment groups over 30 h postoperatively was found to be within the predefined equivalence margin [+7.5/-6.2], and the CI values for pain scores on coughing [+7.3/-9.0] were similar. The two groups did not differ in cumulative opioid rescue consumption (Dipy-Group 14.8 +/- 17.7 mg vs. Para Group 12.1 +/- 8.8 mg, p = 0.54) nor in piritramide loading dose (Dipy Group 0.95 +/- 2.8 mg vs. Para Group 1.3 +/- 2.8 mg, p = 0.545). Five patients in the Dipy Group experienced hypotension in contrast to none in the Para Group (p = 0.047). There were no significant between-treatment differences for other adverse events, patient satisfaction scores (p = 0.4) or quality of recovery scores (p = 0.3).
                IV paracetamol 1 g is clinically equivalent to IV dipyrone 1 g for postoperative analgesia after surgery for breast cancer. The study was to evaluate the analgesic and opioid-sparing effect of intravenous paracetamol injections in cardiosurgical patients in the early postoperative period. Adequate analgesia within the first 12-18 hours of the early postoperative period is very important for a good prognosis of the further course of pain syndrome and for the reduction of a risk for its progression to its chronic form. In early studies, propacetamol lowered morphine use after orthopedic and gynecological operations. The efficacy of paracetamol used in cardiac surgery has been little studied and the results of the studies are conflicting. The randomized, blind, placebo-controlled study included patients after aortocoronary bypass surgery, of them 22 patients received paracetamol and 23 had placebo. The test drug (perfalgan 100 ml or placebo) was intravenously injected 30 min before extubation and then every 6 hours within succeeding 18 hours. The intensity of the pain syndrome was rated by a 5-score verbal scale every 2 hours. With pain score of 2 or more, promedol was intramuscularly administered in a dose of 10 mg. Inspiratory volume was recorded before extubation and the first administration of a drug just after extubation and then every 2 hours. The baseline indices did not differ in both groups. Throughout the observation, the inspiratory volume was lower in the paracetamol group than in the placebo group; however, there was a statistically significant difference (p = 0.012) in the reduction in the manifestations of the pain syndrome (by 81%) only just after tracheal extubation. During this period, inspiratory volume values were higher in the paracetamol group; however, a statistically significant (39%) difference between the groups in the mean values was obtained only during and 2 hours after extubation. In the perfalgan group, the mean total use of promedol was 36% less than in the placebo-group, which was statistically significant (p = 0.019). The early postoperative use of paracetamol after myocardial revascularization reduces the intake of opioids and diminishes the intensity of the pain syndrome within the first hours after extubation, which promotes a higher thoracic excursion, as confirmed by a statistically significant increase in the maximum inspiratory capacity. To compare the analgesic efficacy and tolerance of propacetamol and morphine, 80 patients in good clinical condition were included in a prospective, parallel, randomized double blind trial after elective surgery expected to elicit light to moderate postoperative pain. At the end of general anesthesia, 40 patients received 30 mg/kg propacetamol and 40 0.2 mg/kg morphine, as a 15-min intravenous infusion. The groups were similar for age, weight and duration of anesthesia. Supplemental analgesia had to be given in 7 cases from the propacetamol group vs. 2 cases from the morphine group. The postoperative pain, evaluated 7 times during 4 h from the end of infusion with a visual analog scale, revealed a modest advantage for morphine at 0.5 and 4 h (p = 0.05). The respiratory rate was slightly lower after morphine (p = 0.02). No significant differences were observed in blood oxygen saturation, blood pressure, heart rate, body temperature and vigilance evaluated by the trailmaking test. Nausea was present in 4 cases under propacetamol and 3 under morphine, and pruritus in 2 and 7 cases, respectively. In conclusion, propacetamol may represent an alternative to morphine for pain prevention after mildly to moderately painful surgery in situations where the use of opioids is unsuitable. Despite the widespread use of paracetamol for many years, the analgesic serum concentrations of paracetamol are unknown. Therefore the correlation between serum paracetamol concentrations and the analgesic effect was studied.
                Sixty-four women undergoing laparoscopic sterilization were included in a double-blind, placebo-controlled, randomized study. Patients were given i.v. propacetamol 40 mg kg(-1) (group H), 20 mg kg(-1) (group I), 10 mg kg(-1) (group L) or placebo after surgery. Alfentanil was available via patient-controlled analgesia (PCA) during the 4-h postoperative study period. The patients' self-reported pain was registered on the visual analog scale (VAS). A pharmacokinetic model was fitted to the paracetamol data.
                One to 3 h after injection of propacetamol the alfentanil consumption was significantly (P = 0.01-0.04) higher in the placebo group compared with groups H, I, and L receiving propacetamol. There were no significant differences between the amounts of alfentanil consumed in groups H, I, and L. Initial VAS-scores were moderate (5.4-6.2), and declined significantly (P < 0.0001) over time, with no difference between groups. Paracetamol followed an open two-compartment model with i.v. administration and first order elimination. The estimated concentrations immediately (t = 0) after injection were 56 mg l(-1) (H), 28 mg l(-1) (I) and 14 mg l(-1) (L).
                We showed a significant opioid-sparing effect of paracetamol in the immediate postoperative period. Pharmacokinetic data were in accordance with other studies. Our results suggest that a ceiling effect of paracetamol may be present at i.v. doses of 5 mg kg(-1), i.e. a serum concentration of 14 mg l(-1), which is a lower dose than previously suggested.
                Copyright Acta Anaesthesiologica Scandinavica 47 (2003) Propacetamol is an injectable pro-drug of paracetamol (acetaminophen) with analgesic and antipyretic activities, especially used in the post-operative period. The aim of this study was to assess the analgesic efficacy and safety of intravenous paracetamol, administered as propacetamol, in comparison with placebo and intramuscular diclofenac in patients with post-operative pain.
                This was a randomized, double-blind, double-dummy study. One hundred and twenty patients with moderate to severe pain following total hip arthroplasty received either two administrations of propacetamol 2 g intravenously, 5 h apart (n = 40), one single administration of diclofenac 75 mg intramuscularly (n = 40) or placebo (n = 40). Efficacy measures were assessed before each drug administration, for the 5 h following each study treatment administration and for the total study duration of 10 h. Safety was assessed by reporting adverse events and changes in vital signs, electrocardiogram (ECG) and biochemical investigations before and 24 h after dosing.
                Both active treatments were effective and statistically superior to placebo over the whole study period, as indicated by the total pain relief score. No significant differences were found between propacetamol and diclofenac for any measures of analgesic activity. Only minor and common adverse events were reported, with no overall differences between the groups.
                Both active treatments were superior to placebo, and the overall efficacy of two intravenous infusions of propacetamol 2 g (equivalent to 1 g of paracetamol), 5 h apart, was not statistically different from that provided by a single intramuscular injection of diclofenac 75 mg over the first 5 h post-dose and over the total 10-h study period. The safety was good. Intravenously administered paracetamol is an effective analgesic in postoperative pain management. However, there is a lack of data on the effect of intravenous (i.v.) paracetamol on pain following soft tissue surgery.
                Eighty-seven patients undergoing elective breast surgery with total i.v. anaesthesia (propofol/remifentanil) were randomized to three groups. Group para received 1 g i.v. paracetamol 20 min before and 4, 10 and 16 h after the end of the operation. Group meta and plac received 1 g i.v. metamizol or placebo, respectively, scheduled at the same time points. All patients had access to i.v. morphine on demand to achieve adequate pain relief.
                No significant difference in total morphine consumption between groups was detectable. The proportion of patients who did not receive any morphine in the postoperative period was significantly higher in group para (42%) than in group plac (4%). Ambulation was significantly (P < 0.05) earlier in group para (4.0 +/- 0.2 h) than in groups meta (4.6 +/- 0.2 h) and plac (5.5 +/- 1.0 h). No differences were observed between groups meta and plac. There were no differences between groups with regard to incidence of postoperative nausea and vomiting or changes in vigilance.
                Neither i.v. paracetamol nor i.v. metamizol provided a significant reduction in total postoperative morphine consumption compared with placebo in the management of postoperative pain after elective breast surgery. Administration of paracetamol resulted in a significant reduction in the number of patients needing opioid analgesics to achieve adequate postoperative pain relief. Postoperative pain management after cardiac surgery has been mainly based on parenteral opioids. However, because opioids have numerous side effects, coadministration of non-opioid analgesics has been introduced as a method of reducing opioid dose. In this prospective, randomized, double-blinded study, we evaluated the efficacy of propacetamol, an IV administered prodrug of acetaminophen (paracetamol), as an adjunctive analgesic after cardiac surgery. Seventy-nine patients scheduled for elective coronary artery bypass grafting were randomized to receive either propacetamol 2 g (n = 40) or placebo (n = 39) IV in 6-h intervals for 72 h. From the time of extubation, patients had access to an opioid (oxycodone) via a patient-controlled analgesia device. Pain was evaluated on a visual analog scale four times daily, whereas respiratory function tests (forced vital capacity, forced expiratory volume in 1 s, peak expiratory flow, and arterial blood gas measurements) were performed once a day. The prespecified primary efficacy variable (cumulative oxycodone consumption at the end of the 72-h postoperative period) was 123.5 mg (51.3 mg) (mean [SD]) in the propacetamol group and 141.8 mg (57.5 mg) in the placebo group (difference in mean, 18.3 mg = 13%; 95% confidence interval, 6.1-42.7 mg; P = 0.15). Pain scores did not differ between the groups at rest (P = 0.65) or during a deep breath (P = 0.72). The groups were also similar in terms of pulmonary function tests, postoperative bleeding, and hepatic function tests, and no significant differences were noted in the incidences of adverse effects. After completion of the study, apost hoc analysis was also performed analyzing the first 24 h as split into 6-h intervals. This analysis showed a significantly (P = 0.036) smaller consumption of oxycodone in the propacetamol group at 24 h (47.1 mg [20.7 mg] versus 57.9 mg [23.9 mg]; difference in mean, 10.8 mg; 95% confidence interval, 0.7-20.9 mg). In conclusion, propacetamol did not enhance opioid-based analgesia in coronary artery bypass grafting patients, nor did it decrease cumulative opioid consumption or reduce adverse effects within 3 days after surgery. However, post hoc analysis showed that oxycodone requirement was reduced within the first 24 h in the propacetamol group.
                This is the first placebo-controlled study to investigate the efficacy of propacetamol as a complementary analgesic to opioids after cardiac surgery. Propacetamol did not enhance analgesia, nor did it decrease cumulative opioid consumption or reduce adverse effects in a dose of 2 g given every sixth hour for 3 days after surgery. Intravenous acetaminophen injection (paracetamol) is marketed in Europe for the management of acute pain. A repeated-dose, randomized, double-blind, placebo-controlled, three-parallel group study was performed to evaluate the analgesic efficacy and safety of intravenous acetaminophen as compared with its prodrug (propacetamol) and placebo. Propacetamol has been available in many European countries for more than 20 yr.
                After orthopedic surgery, patients reporting moderate to severe pain received either 1 g intravenous acetaminophen, 2 g propacetamol, or placebo at 6-h intervals over 24 h. Patients were allowed "rescue" intravenous patient-controlled analgesia morphine. Pain intensity, pain relief, and morphine use were measured at selected intervals. Safety was monitored through adverse event reporting, clinical examination, and laboratory testing.
                One hundred fifty-one patients (intravenous acetaminophen: 49; propacetamol: 50; placebo: 52) received at least one dose of study medication. The intravenous acetaminophen and propacetamol groups differed significantly from the placebo group regarding pain relief from 15 min to 6 h (P < 0.05) and median time to morphine rescue (intravenous acetaminophen: 3 h; propacetamol: 2.6 h; placebo: 0.8 h). Intravenous acetaminophen and propacetamol significantly reduced morphine consumption over the 24-h period: The total morphine doses received over 24 h were 38.3 +/- 35.1 mg for intravenous acetaminophen, 40.8 +/- 30.2 mg for propacetamol, and 57. 4 +/- 52.3 mg for placebo, corresponding to decreases of -33% (19 mg) and -29% (17 mg) for intravenous acetaminophen and propacetamol, respectively. Drug-related adverse events were reported in 8.2%, 50% (most of them local), and 17.3% of patients treated with intravenous acetaminophen, propacetamol, and placebo, respectively.
                Intravenous acetaminophen, 1 g, administered over a 24-h period in patients with moderate to severe pain after orthopedic surgery provided rapid and effective analgesia and was well tolerated. To assess clinical efficacy of IV paracetamol 1 g and IV metamizol 1 IV metamizol 1 g on a 24-h dosing schedule in this randomized, double-blinded, placebo-controlled study of 38 ASA physical status I-III patients undergoing retinal surgery.
                General anaesthesia using remifentanil, propofol, and desflurane was performed for surgery. The patients were randomly allocated to three groups, receiving infusions of paracetamol 1 g/100 mL (Para Group), of metamizol 1 g/100 mL (Meta Group), or of 100 mL of saline solution as placebo control (Plac Group) 30 min before arrival in the recovery area and every 6 h up to 24 h postoperatively. All patients had unrestricted access to intravenous opioid rescue medication.
                The primary efficacy variables were pain scores at rest over 30 h postoperatively analysed by using repeated ANOVA measurement. Secondary efficacy variables were pain scores on coughing, also analysed by repeated ANOVA measurement.
                Five patients in the Plac Group and one patient in the Meta Group interrupted the study protocol. Regarding pain scores at rest, Mauchly-test of sphericity was significant (p = 0.03). For the p time effects a significant result was detected (p < 0.001). The main effect between the three treatment groups was significantly different (p = 0.01). The Bonferroni adjusted pair wise comparisons between p the Plac Group and the Para Group showed a significant difference in favour of IV paracetamol (p = 0.024; mean difference 14.8; p 95% CI 1.6-28.0), between the Plac Group and the Meta Group in favour of IV metamizol (p = 0.025; mean difference 14.4; 95% CI p 1.5-27.4), and no significant difference between the Para Group and the Meta Group (p = 1.0; mean difference 0.4; 95% CI-12.8 to 13.6). Pain scores on coughing showed a significant different main effect between the three treatment groups (p = 0.022). The Bonferroni adjusted pair wise comparisons between the Plac Group and the Para Group showed a significant difference in favour of IV paracetamol (p = 0.032; mean difference 17.9; 95% CI 1.3-34.6), a p difference, though not reaching statistical significance, in favour of IV metamizol between the Plac Group and the Meta Group (p = 0.081; p mean difference 15.0; 95% CI -1.4 to 31.4), and no significant difference between the Para Group and the Meta Group (p = 1.0; p mean difference 2.9; 95% CI -13.8 6 to 19.6). None of the patients experienced itching; one patient in the Meta Group developed a mild erythema. There was no statistical difference in the incidence of nausea (Plac vs. Para Group: p = 0.94, Plac vs. Meta Group: p = 0.98, Para vs Meta Group: p = 0.95) or vomiting (Plac vs. Para Group: p = 0.73, Plac vs. Meta Group: p = 0.85, Para vs Meta Group: p = 0.86) between the groups. Patients in the Plac Group experienced significantly more often sedation than patients in the Meta Group (p = 0.049). There was a trend of higher sedation in the Plac Group than in the Para Group, which did not reach statistical significance (p = 0.07). There was no difference in sedation between the Meta and the Para Groups (p = 0.84).
                IV paracetamol 1 g has a similar analgesic potency as IV metamizol 1 g for postoperative analgesia after retinal surgery. Paracetamol, a centrally acting inhibitor of cyclooxygenase, has less gastrointestinal and platelet-inhibiting side effects and is clinically better tolerated than nonsteroidal anti-inflammatory drugs. Therefore, it will be ideally suited for postoperative pain relief. In this prospective, double-blind, randomized, placebo-controlled study, we evaluated the analgesic efficacy, opioid-sparing effect and effects on opioid-related adverse effects of intravenous (IV) paracetamol in combination with IV morphine after lumbar laminectomy and discectomy. Forty patients were divided into 2 groups (n=20 each) to receive either paracetamol 1 g (group 1) or 0.9% NaCl 100 ml (group 2) at the end of the operation and at 6-hour intervals over 24 hours. IV patient-controlled analgesia with morphine was used as a rescue analgesic in both groups. Pain was evaluated at rest and on movement at the 1st, 2nd, 4th, 6th, 12th, 18th, and 24th hours using a visual analog scale. Hemodynamic parameters, morphine usage, patient satisfaction, and probable side effects were also evaluated. Pain scores at rest and on movement at the 12th, 18th, and 24th hours were significantly lower in group 1 (P<0.001). Morphine consumption was not statistically significantly different between the groups (P>0.05). Vomiting in group 2 was significantly higher (P=0.027). Significantly more patients in the paracetamol group rated their pain management as excellent (45% vs. 5%). Although repeated IV paracetamol usage after lumbar laminectomy and discectomy did not demonstrate a significant opioid-sparing effect, it did decrease visual analog scale scores at certain evaluation times and incidence of vomiting and increase patient satisfaction. The analgesic efficacy and safety of propacetamol (Pro-Dafalgan), an injectable prodrug of acetaminophen, in combination with morphine administered by patient-controlled analgesia (PCA) were studied in 60 patients (56 men, 4 women; age 18-40 years; mean age, 26 years) after knee ligamentoplasty. Using a double-blind, randomized, parallel-group design, the effects of four (every 6 hr) intravenous injections of 2 g propacetamol (= 1 g acetaminophen) were compared with four injections of placebo (PL) in the recovery room immediately after surgery. Efficacy was assessed over 24 hr by automatic recording on the PCA device of the cumulative dose of morphine and the number of boluses requested. It was also assessed on pain scores rated on a five-point verbal scale and a visual analogue scale before administration, at 1, 2, 3, and 4 hr, and then every 2 hr until the 24th hr after administration. A five-point global efficacy scale was also administered. Any side effects were recorded throughout the duration of the study, and the ability to tolerate the drug was assessed by recording arterial pressure, cardiac and respiratory frequency, and sedation at the same assessment times as the pain scores. The 24-hr morphine consumption was significantly decreased in the propacetamol group (number of 1 mg boluses: 14.7 +/- 11.3 versus 23.2 +/- 13.8, P = 0.01; PCA usage: 26.4 +/- 12.3 mg versus 34.6 +/- 15.4 mg, P = 0.03; PCA usage + titration: 34.5 +/- 12.7 mg versus 43.1 +/- 15.9 mg, P = 0.02).(ABSTRACT TRUNCATED AT 250 WORDS) Pain after laparoscopic cholecystectomy (LCC) is multifactorial. Effective post-operative pain control is necessary in LCC performed as day-case surgery. We studied the efficacy of paracetamol or valdecoxib with or without dexamethasone after LCC.
                One hundred sixty patients were randomized to four groups of 40 patients. Groups 1 and 3 received parecoxib 40 mg intravenously (IV) during surgery and valdecoxib 40 mg x 1 per os (PO) for 7 post-operative days. Groups 2 and 4 received paracetamol 1 g x 4 IV during surgery and 1 g x 4 PO for 7 days. In addition, Groups 3 and 4 were given dexamethasone 10 mg IV intra-operatively. Propofol and remifentanil were used during surgery. The patients were given oxycodone 0.05 mg/kg IV in phase 1 post-anaesthesia care unit (PACU 1) or 0.15 mg/kg PO in phase 2 post-anaesthesia care unit (PACU 2) as needed to keep visual analogue scale <3/10. The patients were supplied with the study drugs for 7 post-operative days.
                Pain intensity, nausea and the need of oxycodone in phase 1 PACU were similar in all groups. Dexamethasone reduced the need of oral oxycodone in phase 2 PACU (7.0 +/- 1.0 mg vs. 9.1 +/- 1.0 mg, P<0.05). Pain intensity was similar in all groups at home. More patients in the parecoxib/valdecoxib groups needed rescue medication on the 1st post-operative day (P<0.001) than paracetamol-treated patients.
                Paracetamol was as effective as parecoxib/valdecoxib for pain after LCC. Dexamethasone decreased the need of oxycodone in phase 2 PACU. The effect of dexamethasone was similar in paracetamol and parecoxib/valdecoxib patients. The concept of balanced analgesia suggests that a combination of analgesic drugs may enhance analgesia and reduce side effects after surgery. This study evaluated the effect of the combination of propacetamol (Prodafalgan) and ketoprofen (Profenid) after surgery of a herniated disc of the lumbar spine.
                After randomization, 60 patients received: placebo (group 1); 2 g propacetamol (group 2); 50 mg ketoproten (group 3); or a combination of 2 g propacetamol and 50 mg ketoprofen (group 4). Drugs were administered every six hours for two days after surgery. The patients used morphine with patient controlled analgesia pumps (bolus 1 mg; lock out time 10 min) and were evaluated with a visual analogue scale (VAS) at rest and movement every six hours for two days. Side effects were noted.
                The patient characteristics and surgery were identical for each of the four groups. The VAS scores throughout the study were lower in group 4 than in groups 1, 2 and 3 both at rest (P < 0.05) and on movement (P < 0.01). The cumulative dose of morphine at 48 hr was lower in group 4 than in group 1 (23.4 +/- 5 mg vs. 58.9 +/- 9 mg; P < 0.01) or group 2 (23.4 +/- 5 mg vs 43.4 +/- 6.6 mg; P < 0.05) and similar to that in group 3 (34.2 +/- 4.5 mg). The incidence of side effects was similar in all groups.
                The combination of propacetamol and ketoprofen reduced pain scores both at rest and on movement. The drug combination did not reduce the morphine consumption and incidence of side effects. This study evaluated the pre-emptive analgesic effect of intravenous (i.v.) (R)-ketamine in laparoscopic cholecystectomy. (R)-ketamine was used due to the lower incidence of side-effects.
                Sixty patients who underwent surgery under general anesthesia were randomly allocated to 3 groups and studied in a double-blind manner. Two i.v. injections were administered: one after induction of anesthesia, approximately 3 min before surgery, and one after surgery. The placebo group (PLA, n = 20) received saline in both injections. The preoperative group (PRE, n = 20) received (R)-ketamine 1 mg/kg and then saline. The postoperative group (POST, n = 20) received saline and then (R)-ketamine 1 mg/kg. Postoperatively, the patients used a patient-controlled analgesia (PCA) pump. Pain was evaluated with a visual analog scale (VAS) at 30 min and every hour for 4 h and with a verbal rating scale (VRS) at 24 h and after 7 days.
                There were no occurrence of side-effects from (R)-ketamine. VAS and VRS at 1, 2, 3, and 4 h postoperatively showed no statistical differences. In the POST group, extubation was delayed and pain score (VAS) at 30 min postoperatively was significantly lower (P < 0.05) than the two other groups. There were no statistical differences in meperidine consumption during the first 4 h postoperatively and no differences in consumption of analgesics at 24 h and 7 days.
                In this study a 1 mg/kg dose of (R)-ketamine given at the end of surgery exerted a short-lasting hypnotic and analgesic effect. The same dose given preoperatively did not show postoperative analgesic effect or pre-emptive effect. A multimodal approach to postcesarean pain management may enhance analgesia and reduce side effects after surgery. This study evaluates the postoperative analgesic effects of propacetamol and/or diclofenac in parturients undergoing elective cesarean delivery under spinal anesthesia.
                After randomization, 80 healthy parturients received the following: placebo (group M), 100 mg diclofenac rectally every 8 hours (group MD), 2 g propacetamol intravenously every 6 hours (group MP), or a combination of 2 g propacetamol and 100 mg diclofenac (group MDP) as described above. Drugs were administered for 24 hours after surgery. Postoperative pain was controlled with a patient controlled analgesia pump, using morphine. The visual analog scale (VAS) at rest and on coughing, as well as the morphine consumption, were evaluated at 2, 6, and 24 hours postoperatively. Also, the side effects experienced after undergoing the different regimens were compared.
                The patients' characteristics did not differ significantly between the 4 groups. VAS score at 2 hours, both at rest and on coughing were lower in group MDP and MD compared with group M (P <.05). At 24 hours, there was still a tendency toward lower pain scores in the groups MDP and MD; however, this difference was only statistically significant at rest between the MDP group and the MP and M groups. Morphine consumption at 2, 6, and 24 hours was lower in the MDP and MD groups compared with the MP and M groups (P <.05). The morphine-sparing effect was higher in groups MDP and MD compared with group MP (57% and 46%, respectively, v 8.2%, P <.05). The incidence of side effects was similar in all groups. However, the power of the study was too low to permit an evaluation of potential side effects.
                Diclofenac after cesarean delivery improves analgesia and has a highly significant morphine-sparing effect. We were unable to demonstrate significant morphine-sparing effect of propacetamol or additive effect of propacetamol and diclofenac in this group of patients. We compared the efficacy and side effects of propacetamol (P), an injectable prodrug of acetaminophen, 2 g and tramadol (T), a weak synthetic opioid, 1.5 mg.kg-1, given intravenously following thyroidectomy. 80 patients were randomly assigned to blindly receive one dose of P or T on request in the PACU. Residual pain was treated with i.v. PCA morphine. Pain and patient satisfaction were assessed with Visual Analog Scales. Demographic and peroperative data were comparable in both groups. Although the morphine consumption was comparable (p = 0.71), the decrease in VAS pain scores was significantly higher following tramadol (p = 0.03). More patients complained of nausea and vomiting (p = 0.01) during the first two hours following injection of tramadol, but there was no difference throughout the whole study. Oversedation was not observed in any group. We conclude that a single dose of tramadol provides a better quality of analgesia than propacetamol during the first six hours after thyroidectomy, but fails to ensure optimal analgesia, since VAS pain scores failed to fall below 3 despite the use of supplemental morphine. Combined analgesic regimens have been suggested to improve the treatment of postoperative pain. The aim of our study was to evaluate the analgesic efficacy and tolerability of propacetamol, in combination with morphine.
                Four i.v. infusions of propacetamol 2 g or placebo were administered, in a double-blind fashion, after orthopedic surgery (n = 97). Morphine was administered by a patient-controlled analgesia (PCA) device. The total dose of morphine, pain intensity and global efficacy of treatment were evaluated. Tolerability was assessed by monitoring blood pressure, heart and respiratory rate, sedation scores, adverse events, and renal and hepatic parameters.
                The total dose of morphine was significantly decreased in the propacetamol group compared to placebo (9.4 +/- 8.5 mg vs 17.6 +/- 12 mg; P < 0.001), arriving at a sparing effect of 46%. The evolution of pain intensity showed a similar pattern in the two groups. Global efficacy of treatment was rated significantly better by patients receiving the combination propacetamol + PCA morphine (87% of "good"/"excellent" ratings vs 65%; P = 0.01). Tolerability was comparable in the two groups. Eight patients in the propacetamol and 4 patients in the placebo group reported adverse events, of mild/moderate intensity, most commonly nausea/vomiting. Renal and hepatic parameters were also seen to be comparable.
                These results confirm a significant morphine-sparing effect, significantly better scores in the final assessment by patients, and a good tolerability of propacetamol after orthopedic surgery. The drug may, therefore, represent a useful alternative to NSAIDs, as complementary drug to opioids, in the management of moderate/severe postoperative pain. To compare the postoperative analgesic efficacy and safety of the non-addictive propacetamol hydrochloride (Pro-Bufferin) injection and dolantin in a prospective, randomized, double blind and controlled clinical trial.
                After the pain intensity was assessed when the patients were undergone thoracic and abdominal selective surgery became fully conscious, 40 consecutive patients with moderate to severe postoperative pain (equivalent to Pain Grade I and II of American Anesthesia Association classification) were randomized into the study against the control groups. The two groups were similar for age, sex, height/weight, disease categories, operation categories, anesthesia methods and duration, vital signs, hepatorenal function, and blood cell count (P = 0.06-0.93). In the study group, 2 g propacetamol in 100 ml normal saline (NS) intravenously with 1.0 ml NS intramuscularly as the placebo control to dolantin were administered. In the control group, 1.6 g mannitose in 100 ml NS intravenously as the placebo control to propacetamol with 50 mg dolantin (1.0 ml) intramuscularly as the positive control to propacetamol were administered. The intensity change of postoperative pain was then evaluated 10 times with visual analog scale and verbal describing scale during 6 h from the beginning of propacetamol infusion. Vital signs and adverse reactions were also documented. After all data were put into the computer, the blinding codes were decoded and the statistic analysis was then made.
                There was no significant difference (P = 0.93) about the area under the curve of "Pain Relieve Score vs. Time". The "starting to effect" time (15-30 min), analgesic duration (6 h) and the percentage of excellent or good analgesic effect (90%) in the two groups were the same. Adverse reactions didn't reached the statistic different level (P = 0.35).
                Propacetamol HCL injection 2 g intravenously could be an alternative to dolantin 50 mg intramuscularly for moderate to severe postoperative pain with its advantage of being non-addictive. To evaluate both effectiveness and incidence of side effects of two techniques of postoperative pain treatment: intravenous and epidural PCA.
                Prospective analysis of data from two groups of randomized patients.
                Orthopedic and trauma center.
                Figty ASA class II-III patients undergoing total hip replacement under combined Spinal-Epidural Anesthesia.
                Patients were divided into 2 groups who received different postoperative pain treatment. One group (group PCA) received a patient-controlled intravenous analgesia with morphine 30 mg and ketorolac 90 mg in 100 ml of saline (back-ground infusion 2-4 ml, according to body weith, bolus 1 ml, lockout 5 min, 4 h dose limit 40 ml). PCEA group received a patient-controlled epidural analgesia with morphine 4 mg and bupivacaine 0.125% 100 ml, (background infusion 3-4 ml, according to patient' height, bolus 1 ml, lockout 10 min, 4 h dose limit 25 ml). Postoperative pain intensity was evaluated, through 24 postoperative hours, by a verbal analogue scale (VPS = 0 to 3) and a total pain score (TOTPAR) was calculated for each patient at 6 and 24 postoperative hours. Side effects were recorded and their incidence was obtained for each group. Statistical data analysis was performed by one-way ANOVA and non-parametric tests for ordinal data. Nominal data were analyzed by chi 2 test. p < 0.05 was considered significant.
                Patient receiving PCEA showed a significant (p < 0.005) decrease of incident pain, while VPS at rest was similar in the two groups. TOTPAR VPS was lower (p < 0.05) in PCEA group both at 6 and 24 postoperative hours. Somnolence was observed more often in PCA patients (8% vs 2%; p 0.05), while no significant differences were noted among other side effects incidence.
                Our data show a better control of postoperative pain arising from total hip replacement during PCEA when compared to PCA. It should be emphasized that incident pain is far more decreased by PCEA, so that this technique is particularly indicated when an early postoperative mobilization is required. We assessed the analgesic efficacy of IV propacetamol and ketorolac in a double-blinded, placebo-controlled study involving patients undergoing total hip or knee replacement procedures. On the first morning after major joint replacement surgery, 164 patients experiencing moderate-to-severe pain were randomly assigned to receive an IV infusion of propacetamol (2 g), ketorolac (15 or 30 mg), or placebo (saline). Patient-controlled analgesia with morphine was made available as a "rescue" analgesic on patient's request during the 6-h postdosing evaluation period. The median time to onset of analgesia with propacetamol (8 [95% confidence interval 6,10] min) was shorter than ketorolac 15 mg (14 [7,16] min), and placebo (16 [8; not estimable] min) although the differences did not reach statistical significance. However, compared with ketorolac 30 mg, propacetamol had a shorter duration of analgesia (3.5 [2;5.4] vs 6 [3.3; not estimable] h). Analysis of pain intensity and pain relief scores demonstrated that propacetamol produced a significantly greater improvement in pain relief than saline from 45 min until 5 h after the injection. Propacetamol was not significantly different from ketorolac 15 mg and 30 mg with respect to the main analgesic efficacy variables during the 6-h assessment period. The most frequently reported adverse event with propacetamol was injection site pain (28% vs 19% for ketorolac 15 mg, 29% for ketorolac 30 mg, and 10% for placebo, respectively). In conclusion, propacetamol (2 g IV) possesses a similar analgesic efficacy to ketorolac (15 or 30 mg IV) after total hip or knee replacement surgery. The purpose of this randomized double-blind study was to compare the efficacy and safety of propacetamol 2 g (an i.v. acetaminophen 1 g formulation) administered as a 2-min bolus injection (n=50) or a 15-min infusion (n=50) with oral acetaminophen 1 g (n=50) or placebo (n=25) for analgesia after third molar surgery in patients with moderate to severe pain after impacted third molar removal.
                All patients were evaluated for efficacy during the initial 6 h period after treatment administration (T(0)) and for safety during the entire week after T(0).
                The onset of analgesia after propacetamol was shorter (3 min for bolus administration, 5 min for 15-min infusion) than after oral acetaminophen (11 min). Active treatments were significantly better for all parameters (pain relief, pain intensity, patient's global evaluation, duration of analgesia) than placebo (P<0.05). Adverse events were more frequent after propacetamol, especially pain at the injection site. Propacetamol bolus resulted in a much higher incidence of local adverse events than the infusion (propacetamol bolus 90% vs propacetamol infusion 52%) with no clinically significant benefits in terms of analgesic efficacy.
                I.V. propacetamol, administered as a 15-min infusion, is a fast-acting analgesic agent. It is more effective in terms of onset of analgesia than a similar dose of oral acetaminophen. A randomized, double-blind, placebo-controlled single oral dose study was done in order to examine whether codeine has an additive analgesic effect to that of paracetamol for moderate and strong postoperative pain after abdominal surgery. The maximum recommended single dose of paracetamol 1000 mg (Paracet) was compared with a combination of a submaximal dose of paracetamol 800 mg plus codeine 60 mg (Paralgin forte) and placebo for pain relief after Caesarean section in 125 patients.
                Visual analogue pain intensity score (VAS 0-100 mm) and categorical pain relief score were recorded for 6 hours after the study drug intake. The main efficacy variables analyzed were: pain intensity difference and summed pain intensity differences during the first 3 and 6 h after study drug intake, total pain relief during the first 3 and 6 h, global evaluation score at the end of the observation period, and time to rescue analgesic.
                Because of protocol violations, 17 patients were excluded from the analysis of effects. Among the 108 patients included in the analysis of analgesic effect, 49 patients had moderate baseline pain (VAS between 40 and 60 mm on a 100 mm scale), and 59 patients had strong baseline pain (VAS more than 60 mm). In patients with strong baseline pain, statistically highly significant differences were documented in efficacy variables between the active drugs and placebo and between the two active drugs. However, in patients with moderate baseline pain, no differences were found between the study drugs in any of the analgesic efficacy variables.
                This study thus confirms that codeine has additive analgesic effect to paracetamol in pain after surgery. Our results show the importance of initial pain intensity in postoperative assessment of analgesic drugs. Assay-sensitivity and test power are increased by selecting patients with sufficiently high initial pain intensity and by comparing groups of patients with identical surgery and similar demographic variables. Diclofenac and paracetamol have different mechanisms and sites of action. Therefore, we tested if their combination is more effective for analgesia after tonsillectomy than either drug alone with respect to rescue analgesic consumption and visual analog scale values.
                The analgesic effects of intravenously administered propacetamol (injectable pro-drug of paracetamol) and diclofenac or a combination on postoperative pain were compared in 71 adult elective tonsillectomy patients in a randomized, double-blind study. After induction of anesthesia the patients received monotherapy with 2 g propacetamol (n = 25) or 75 mg diclofenac (n = 25), or a combined treatment with 2 g propacetamol and 75 mg diclofenac (n = 21) in physiologic saline as an infusion. Postoperatively the propacetamol dosage was repeated twice and diclofenac once on the ward. Oxycodone (0.03 mg kg(-1)) was used as a rescue analgesic by patient-controlled analgesia.
                On average the patients needed oxycodone 15.3, 13.2 and 10.6 times in the propacetamol, diclofenac and combination groups, respectively (NS). A verbal rating scale and a visual analog scale were employed for assessing post-tonsillectomy pain, nausea and patient satisfaction in all groups. No statistically significant differences were found between the groups. Twelve of the 25 (48%) patients having received propacetamol complained of pain at the cannulation site.
                Combined treatment with propacetamol and diclofenac with the dosages used provided clinically only a minor advantage over monotherapy with propacetamol or diclofenac with respect to postoperative analgesia or the incidence of side-effects in adult tonsillectomy patients. Outpatient surgery demands rapid recovery and satisfied patients. The purpose of the study was to investigate whether rectal premedication with paracetamol and codeine would reduce the need of rescue analgesics, reduce the postoperative pain experience and result in faster eligibility for discharge. Ninety pregnant patients scheduled for day-case surgery with evacuation of the uterine cavity were randomly assigned into two groups. The paracetamol and codeine group was given a suppository with 60 mg of codeine and 800 mg of paracetamol together with standard premedication of intramuscular midazolam 0.08 mg/kg. The placebo group was given a placebo suppository and midazolam. All patients underwent the surgical procedure under general anaesthesia with alfentanil 15 microg/kg and propofol 1.5-2 mg/kg. There were no statistically significant differences between the groups in the postoperative pain experience as judged by Visual Analogue Scale (VAS-scale), verbal scale or the need for rescue analgesic medication with ketobemidone. Most of the patients experienced little postoperative pain with more than 70% scoring less than 20 mm on a VAS-scale from 0-100 mm at any time during the postoperative period. The paracetamol and codeine patients were significantly more sleepy at 30 min postoperatively. There were no differences between the groups in postoperative nausea or vomiting and no difference in discharge eligibility. The use of pre-operative suppository with paracetamol 800 mg and codeine 60 mg is unnecessary in this group of patients.
                Copyright 2000 European Federation of Chapters of the International Association for the Study of Pain. Several reports have suggested that preoperative nociceptive block may reduce postoperative pain, analgesic requirements, or both, beyond the anticipated duration of action of the analgesic agents. We have investigated, in a double-blind, placebo-controlled study, pre-emptive analgesia and the respiratory effects of preoperative administration of a multimodal antinociceptive regimen. Thirty patients undergoing thoracotomy were allocated randomly to two groups. Before surgery, the treatment group (n = 15) received morphine 0.15 mg kg-1 i.m. with perphenazine 0.03 mg kg-1 i.m. and a rectal suppository of indomethacin 100 mg, while the placebo group (n = 15) received midazolam 0.05 mg kg-1 i.m. and a placebo rectal suppository. After induction of anaesthesia, the treatment group received intercostal nerve block with 0.5% bupivacaine and adrenaline 1:200,000 (3 ml) in the interspace of the incision and in the two spaces above and two spaces below. The placebo group received identical injections but with normal saline only. The treatment group consumed significantly less morphine by patient-controlled analgesia in the first 6 h after operation, but the total dose of morphine consumed on days 2 and 3 after surgery was significantly greater in the treatment group. There were no differences between the groups in postoperative VAS scores (at rest or after movement), PaCO2 values or postoperative spirometry. However, pain thresholds to pressure applied at the side of the chest contralateral to the site of incision decreased significantly from preoperative values on days 1 and 2 after surgery in both groups. The results of this study do not support the preoperative use of this combined regimen for post-thoracotomy pain. We compared the effects of rectally administered diclofenac (12.5 mg) with paracetamol (125 mg) on pre- and postoperative behaviour and the need for supplementary analgesia in 44 children scheduled for adenoidectomy (with or without myringotomy). The study drugs were given in combination with diazepam (0.5 mg.kg-1) about 20 min before the children were taken to the operating theatre. On arrival there, the children who had received diclofenac were significantly quieter (< 0.05), easier to handle (p < 0.01) and cried less (p < 0.05) than those in the paracetamol group. During recovery, children in the diclofenac group needed fewer supplementary doses of intravenous pethidine than those receiving paracetamol (p < 0.001). There were no obvious differences between the groups in intra-operative bleeding (as estimated by the surgeon), or in measured blood loss. No postoperative complications became evident. The pre-operative rectal administration of diclofenac for pain relief after adenotomy is safe and effective. The aim of the study was to compare the efficacy of parecoxib for postoperative analgesia after endoscopic turbinate and sinus surgery with the prodrug of acetaminophen, proparacetamol.
                Fifty American Society of Anesthesiology (ASA) physical status I-II patients, receiving functional endoscopic sinus surgery (FESS) and endoscopic turbinectomy, were investigated in a prospective, randomized, double-blind manner. After local infiltration with 1% mepivacaine, patients were randomly allocated to receive intravenous (i.v.) administration of either 40 mg of parecoxib (n=25) or 2 g of proparacetamol (n=25) 15 min before discontinuation of total i.v. anaesthesia with propofol and remifentanil. A blinded observer recorded the incidence and severity of pain at admission to the post anaesthesia care unit (PACU) at 10, 20, and 30 min after PACU admission, and every 1 h thereafter for the first 6 postoperative h.
                The area under the curve of VAS (AUC(VAS)) calculated during the study period was 669 (28-1901) cm x min in the proparacetamol group and 635 (26-1413) cm x min in the parecoxib group (p=0.34). Rescue morphine analgesia was required by 14 patients (56%) in the proparacetamol group and 12 patients (48%) in the parecoxib (p >or= 0.05), while mean morphine consumption was 5-3.5mg and 5-2.0 mg in the proparacetamol groups and parecoxib, respectively (p >or= 0.05). No differences in the incidence of side effects were recorded between the 2 groups. Patient satisfaction was similarly high in both groups, and all patients were uneventfully discharged 24 h after surgery.
                In patients undergoing endoscopic nasal surgery, prior infiltration with local anaesthetics, parecoxib administered before discontinuing general anaesthetic, is not superior to proparacetamol in treating early postoperative pain. In a randomized, double-center, double-blind, parallel group study the analgesic effect of a single dose of paracetamol (1000 mg) and acetyl salicylic acid (1000 mg) was compared with placebo in patients with moderate to severe postoperative pain following the surgical removal of a wisdom tooth. The most important finding was the statistically significantly shorter period until the onset of the action of paracetamol as against acetyl salicylic acid.
A single dose of both IV propacetamol and IV paracetamol provides around four hours of effective analgesia for about 37% of patients with acute postoperative pain. Both formulations are associated with few adverse events, although patients receiving IV propacetamol have a higher incidence of pain on infusion than both placebo and IV paracetamol.