Effectiveness of quinine in treating muscle cramps: a double-blind, placebo-controlled, parallel-group, multicentre trial. Treatment of nocturnal leg cramps. A crossover trial of quinine vs vitamin E. Placebo-controlled trial of quinine therapy for nocturnal leg cramps. Prevention of muscle cramps in haemodialysis patients by quinine sulphate. Randomised controlled trial of hydroquinine in muscle cramps. Managing nocturnal leg cramps--calf-stretching exercises and cessation of quinine treatment: a factorial randomised controlled trial. A randomized controlled trial of quinidine in the treatment of cirrhotic patients with muscle cramps. [Treatment of nocturnal leg cramps. A multicenter, double blind, placebo controlled comparison between the combination of quinine and theophylline ethylene diamine with quinine]. Dialysis leg cramps. Efficacy of quinine versus vitamin E. N-of-1 trials of quinine efficacy in skeletal muscle cramps of the leg. A quinine a day keeps the leg cramps away? A double-blind comparison of quinine sulphate and placebo in muscle cramps. Randomized comparison of quinine-clindamycin versus artesunate in the treatment of falciparum malaria in pregnancy. Efficacy of hydroquinine in preventing frequent ordinary muscle cramp outlasts actual administration. Effective treatment of uncomplicated Plasmodium falciparum malaria with azithromycin-quinine combinations: a randomized, dose-ranging study. Quinine loading dose in severe Falciparum malaria at Kenyatta National Hospital, Kenya.
To determine the efficacy and safety of quinine in treating nocturnal muscle cramps we performed a double-blind, placebo-controlled, parallel-group, multicentre trial in 17 general practice centres in Germany. Ninety-eight patients aged 18-70 years with more than six muscle cramps in two weeks were enrolled. A two-week run-in period without treatment was followed by two weeks of treatment with 400 mg quinine or placebo per day and a wash-out period of two weeks without treatment. The primary outcome measure was the reduction in the number of muscle cramps between the run-in and treatment periods. The intensity of cramps, number of nights with cramps, sleep disturbance and intensity of pain were recorded as secondary outcome measures. At baseline the median number of cramps was 12 in two weeks in both groups. The median reduction between the run-in and therapy phases was eight (95% CI 7-10) versus six (95% CI 3-7) muscle cramps during quinine and placebo treatment; 36 (80%) participants in the quinine group and 26 (53%) in the placebo group had a reduction of at least 50% in the number of muscle cramps. Frequency, intensity and pain at night showed a statistically significant difference in favour of quinine. The improvement was more evident according to physician assessment than patient assessment; this is corroborated by the high placebo response rate. No significant differences were found between the two groups with respect to side-effects. Short term treatment with 400 mg quinine per day can effectively prevent nocturnal leg cramps in adults without relevant side-effects. This study compared the efficacy and safety of quinine sulfate, vitamin E, and placebo in the treatment of nocturnal leg cramps.
                A random-order, double-blind, placebo-controlled crossover trial was performed.
                The study was conducted at the Veterans Affairs Medical Center, White River Junction, Vt.
                Twenty-seven male veterans, aged 38 to 73 years, who experienced at least six leg cramps per month were recruited through the general medicine walk-in clinic or were referred from other clinics. Fifty-five subjects were contacted, 30 were enrolled consecutively, and 27 completed the study.
                Subjects received, in random order, quinine sulfate (200 mg at supper and 300 mg at bedtime), vitamin E (800 U at bedtime), or placebo for 4-week periods. These periods were separated by 4-week washout intervals.
                Patients reported cramp frequency, severity, and sleep disturbance caused by cramps.
                Compared with treatment with placebo, quinine reduced the frequency of cramps and sleep disturbance, but not the average cramp severity. Thirteen of 27 patients had at least a 50% reduction in the number of cramps while receiving quinine; the response was usually seen within 3 days. There was evidence of a mild increase in side effects while subjects received quinine. Vitamin E was not effective in reducing leg cramp frequency, severity, or sleep disturbance.
                Quinine sulfate, but not vitamin E, is superior to placebo in the treatment of nocturnal leg cramps. A prospective, double-blind, placebo-controlled crossover study of the use of quinine for nocturnal leg cramps was carried out in 8 elderly volunteer patients. The patients were randomly assigned to receive either placebo or 200 mg of quinine sulfate by mouth at bedtime. After 4 weeks of treatment and after a one-week washout period, the group taking quinine switched to placebo and vice versa for another 4 weeks. The differences in the number, duration, and severity of cramps and the side effects were compared. All of the patients had fewer cramps and decreased severity and duration of attacks while receiving quinine. Mild side effects developed in only 2 patients, and these subsided without treatment or discontinuing the medication. We conclude that quinine was effective in relieving nocturnal leg cramps in a selected group of elderly patients. Nine patients on maintenance haemodialysis with frequent muscle cramps were given 320 mg quinine sulphate or placebo (in an identical gelatin capsule) at the beginning of each dialysis for a period of 12 weeks. The frequency of cramps was significantly reduced during dialysis in patients receiving quinine sulphate. None of the haematological, auditory, or visual disturbances ascribed to quinine sulphate were noted. Although quinine and hydroquinine are commonly prescribed for muscle cramps, controlled clinical trials of these drugs have reported mixed findings about efficacy. We investigated hydroquinine therapy in otherwise healthy adults who had frequent, ordinary muscle cramps.
                This randomised, double-blind, placebo-controlled, parallel-group trial consisted of three consecutive 2-week periods: qualification, treatment, and washout, 68 women and 44 men who had at least three muscle cramps per week were enrolled. During the treatment period, participants were randomly assigned 300 mg daily dose of hydroquinine hydrobromide dihydrate (54 participants) or placebo (58). The frequency, severity (1-10), duration, and location of muscle cramps, as well as any side-effects, were recorded by participant in daily diaries. The primary outcome measures were the number of muscle cramps and the number of days during which the participants had muscle cramps (cramp-days).
                We excluded five participants from both groups from the analysis. Thus, data from 49 hydroquinine-group participants and 53 placebo-group participants were analysed. In both groups the total number of muscle cramps and the number of cramp-days decreased during the treatment period compared with the qualification period. However, these improvements were greater in the hydroquinine group than in the placebo group. The hydroquinine-group participants reported a median of 8 (95% CI 7-12) fewer cramps and median of 3 (1-4) fewer cramp-days, whereas those on placebo reported only 3 (0-5) fewer cramps and 1 (0-5) fewer cramp-days. 32 (65%) of participants in the hydroquinine group had a 50% or greater reduction in the number of muscle cramps. After the onset of cramps, hydroquinine did not reduce the severity or duration of cramps. We also found a sustained effect after treatment had stopped. Hydroquinine was well tolerated, and resulted in only mild side-effects.
                In our study, 300 mg hydroquinine was safe to take in the short-term and significantly more effective than placebo in the prevention of frequent, ordinary muscle cramps. This therapeutic effect outlasted the duration of treatment. Quinine is a common treatment for nocturnal leg cramps but has potential side effects. An uncontrolled study suggested that calf-stretching exercises could prevent nocturnal leg cramps (night cramps) but these findings have never been confirmed.
                To assess the effect of calf-stretching exercises and cessation of quinine treatment for patients with night cramps taking quinine.
                Randomised controlled trial.
                Twenty-eight general practices in southern England.
                One hundred and ninety-one patients prescribed quinine for night cramps were randomised to one of four groups defined by two "advice" factors: undertake exercises and stop quinine. After 6 weeks they were advised that they could take quinine and undertake the exercises freely. Documentation of cramp at 12 weeks was achieved in 181 (95%) patients. Main outcome measures were: symptom burden score, and frequency of night cramps and quinine usage.
                At 12 weeks there was no significant difference in number of cramps in the previous 4 weeks (exercise = 1.95, 95% confidence interval [CI] = -3.01 to 6.90; quinine cessation = 3.45, 95% CI = -1.52 to 8.41) nor symptom burden or severity of cramps. However, after 12 weeks 26.5% (95% CI = 13.3% to 39.7%) more patients who had been advised to stop quinine treatment reported taking no quinine tablets in the previous week (odds ratio [OR] = 3.32, 95% CI = 1.37 to 8.06), whereas advice to do stretching exercises had no effect (OR = 0.73, 95% CI = 0.27 to 1.98).
                Calf-stretching exercises are not effective in reducing the frequency or severity of night cramps. Advising those on long-term repeat prescriptions to try stopping quinine temporarily will result in no major problems for patients, and allow a significant number to stop medication. In an attempt to evaluate the effect of quinidine in the treatment of patients with cirrhosis and muscle cramps, 31 cirrhotic patients with muscle cramps were randomly divided into two groups and given orally 400 mg of quinidine sulfate per day or placebo, respectively. Baseline clinical and laboratory data for these two groups were similar. Four weeks after oral administration of quinidine, the number of cramps significantly decreased from 14.4 +/- 1.7 (mean +/- S.E.) to 4.4 +/- 1.1 episodes (p less than 0.0001), but it remained unchanged in the placebo group (from 11.8 +/- 1.0 to 11.5 +/- 1.5 episodes, p greater than 0.05). In addition, 88% of the 16 patients on quinidine and 13% of the 15 patients on a placebo showed a greater than 50% reduction in the number of cramps during a 4-week treatment period (p less than 0.0001). The peak and trough serum levels of quinidine in patients having received quinidine for 2 weeks were 1.3 +/- 0.1 and 0.7 +/- 0.1 mg/l, respectively. There was a significant relationship between serum quinidine concentrations and attenuation of cramps. No significant adverse effect was observed during the study, except for five (31%) patients who developed mild diarrhea after quinidine therapy. Diarrhea subsided spontaneously or was controlled by medications without the interruption of quinidine therapy. It was concluded that quinidine is a safe and effective drug for the treatment of cirrhotic patients with muscle cramps. 164 patients (m = 45, w = 119; age 55.7 +/- 14.7 years) took part in a multicentric controlled parallel-double blind study in which efficacy and tolerability of the combination quinine sulfate (CAS 6119-70-6) plus theophylline ethylene diamine (CTED, CAS 317-34-0) (Limptar) in the treatment of the recurrent nocturnal leg cramps were investigated. Only patients who suffered before the begin of the study in at least three nights per week from leg cramps were included. The duration of the study was three weeks. In the first week all patients were treated in a single blind design with placebo. The subsequent 2 weeks were carried out double-blind. The global efficacy judged by the physicians and investigated for the 126 patients who took the compounds at least four days within the random phase was remarkably better for the combination than for quinine or placebo (very good and good in 87.1 vs. 63.7 vs. 39.5% of the cases; p less than 0.001; x-test). In 117 patients an analysis of the time course of the efficacy could be done from the notes in the diary (minimum duration of treatment 11 d). Already within the first week there was a highly significant decrease of nights with leg cramps within the CTED group (n = 34) from 4.68 (95% confidential interval 2.26-7.0) to 2.25 (0-6.78) in comparison to placebo (n = 40; from 4.32 [1.9-7.0] to 3.69 [1.22-6.91]) and quinine (n = 43; from 4.78 [2.22-7.0] to 3.27 [0-7.0]; F-test; p = 0.0001 resp. 0.0012).(ABSTRACT TRUNCATED AT 250 WORDS) A controlled randomized double-blind study was done to determine the frequency and severity of leg cramps in 40 patients on dialysis with a history of leg cramps. All patients entered a 2 month placebo washout and were randomized into a 2 month double-dummy phase of quinine 325 mg at bedtime versus vitamin E 400 IU at bedtime. Of the 29 patients completing the study, 16 received quinine and 13 vitamin E. During placebo washout, the vitamin E group had a mean of 10.4 leg cramps per month, and the quinine group had a mean of 10.9. The vitamin E and quinine groups had a 1 month reduction in leg cramps to 3.3 and 3.6, respectively (p < 0.0005 for both groups combined); this was sustained at 2 months. A severity of pain index showed a statistically significant decrease for both groups. The 95% confidence interval for the difference between the number of leg cramps after vitamin E versus quinine treatment (95% confidence interval, -3.8, +3.2) suggests similar efficacy. Quinine and vitamin E were effective treatments for leg cramps in these patients. Considering the potential toxicity of quinine, vitamin E is recommended as the initial treatment of choice for patients on dialysis with leg cramps. Skeletal muscle cramps affect over a third of the ambulatory elderly population. Quinine is the established treatment, but there are safety concerns, and evidence for efficacy is conflicting. A recent meta-analysis established a small advantage for quinine, but identified the need for additional studies. N-of-1 trials compare two treatments, in a randomised, double-blind, multiple crossover study on a patient-by-patient basis. They have been used to compare treatments in osteoarthritis and may be suitable for determining the individual efficacy of quinine.
                To establish efficacy and safety of quinine sulphate use for the treatment of leg-muscle cramp.
                Double-blind, randomised series of n-of-1 controlled trials of quinine versus placebo for muscle cramps.
                New Zealand general practices.
                The participants were 13 general practice patients (six males; seven females; median age = 75 years) already prescribed quinine. Following a 2-week washout, each patient received three 4-week treatment blocks of quinine sulphate and matched placebo capsules with an individual, randomised crossover design. The main outcome measures were: patient diaries of cramp occurrence, duration and severity; capsule counts; and blood quinine levels in the final treatment block.
                Ten patients completed the trial. Three patients were identified for whom quinine was clearly beneficial (P <0.05), six showed non-significant benefit and one showed no benefit. All patients elected to continue quinine post-study.
                Series of n -of-1 studies differentiated patients whom quinine had statistically significant effects; those with trend towards effectiveness; those for whom quinine was probably not effective. Ideally n-of-1 trial should be performed when a patient is commenced on quinine. More cycles in n-of-1 studies of quinine may address issues of statistical power. A double-blind, placebo-controlled, cross-over trial of quinine in leg cramps occurring at rest was conducted in 22 elderly cramp sufferers. Despite demonstration of impaired quinine elimination in the elderly, prescription of the traditional dose of 300 mg quinine bisulphate at night failed to produce a significant (P = 0.1) reduction in the number or severity of cramps. There was a significant relationship between serum quinine concentration and attenuation of cramps. However, the simple expedient of increasing the nightly dose of quinine may carry the concomitant risk of cinchonism. Muscle cramps are painful and common in elderly patients but have largely escaped medical investigation. Quinine sulphate is usually the sole drug prescribed, even though firm evidence for its efficacy is not available. The results of the present double-blind cross-over study show that quinine was significantly superior to placebo in decreasing the number, severity and duration of nocturnal cramps. Since quinine is not a primary drug in any other condition, further studies of drugs with similar pharmacological actions may thus improve our management of this painful complaint. In areas where multidrug-resistant Plasmodium falciparum (MDR-Pf) is prevalent, only quinine is known to be safe and effective in pregnant women. On the western border of Thailand, 7 days of supervised quinine (30 mg/kg daily) cures two-thirds of P. falciparum-infected women in the 2nd and 3rd trimesters of pregnancy. Artesunate is effective against MDR-Pf and the limited data on its use in pregnancy suggest it is safe. An open randomized comparison of supervised quinine (10 mg salt/kg every 8 h) in combination with clindamycin (5 mg/kg every 8 h) for 7 days (QC7) versus artesunate 2 mg/kg per day for 7 days (A7) was conducted in 1997-2000 in 129 Karen women with acute uncomplicated falciparum malaria in the 2nd or 3rd trimesters of pregnancy. There was no difference in the day-42 cure rates between the QC7 (n = 65) and A7 (n = 64) regimens with an efficacy of 100% in both, confirmed by parasite genotyping. The A7 regimen was also associated with less gametocyte carriage; the average person-gametocyte-weeks for A7 was 3 (95% CI 0-19) and for QC7 was 39 (95% CI 21-66) per 1000 person-weeks, respectively (P < 0.01). There was no difference in gastrointestinal symptoms between the groups but there was significantly more tinnitus in the QC7 group compared to the A7 group (44.9% vs 8.9%; RR 5.1; 95% CI 1.9-13.5; P < 0.001). The favourable results with quinine-clindamycin mean that there is a useful back-up treatment for women with falciparum malaria who experience quinine and artesunate failures in pregnancy. Adherence to the 7-day regimen and cost (US$18.50 per treatment) are likely to be the main obstacles to this regimen. In order to compare the efficacy of a daily dose of 300 mg hydroquinine hydrobromide and placebo in preventing frequent ordinary muscle cramp, we designed a randomized, double-blind, placebo-controlled study of three consecutive 2-week periods viz. a qualification period, a medication period and a wash-out period. Twenty healthy adult volunteers experiencing at least 3 muscle cramps a week (6 men, 14 women aged 38-78 yrs) were enrolled into this study, and 19 of them completed it. Hydroquinine hydrobromide (300 mg/day) was administered to group 1 (10 women) and placebo to group 2 (4 women, 6 men). The frequency, severity, duration and location of muscle cramps as well as short-term adverse drug effects were recorded in daily diaries. Compared with placebo the decrease in the mean number of muscle cramps (16.1 or 58%) in the active drug treatment group during the medication period was highly significant (Wilcoxon test p = 0.004). During the wash-out period this decrease partly persisted (8.9 or 33%). In this study a daily dose of 300 mg hydroquinine hydrobromide was effective in preventing frequent ordinary muscle cramp in healthy female volunteers. The effects of hydroquinine outlasted its administration. The drug was well tolerated. Azithromycin, the most potent antimalarial macrolide antibiotic, is synergistic with quinine against Plasmodium falciparum in vitro. We assessed combinations of azithromycin and quinine against uncomplicated P. falciparum malaria at the Armed Forces Research Institute of Medical Sciences-Kwai River Clinical Center along the Thailand-Myanmar border, an area with a high prevalence of multidrug-resistant P. falciparum. Four regimens were assessed in an open-label dose-ranging design involving 61 volunteers. All received oral quinine (Q; 30 mg/kg/day divided every 8 hours for 3 days) with oral azithromycin (Az; 500 mg twice a day for 3 days, 500 mg twice a day for 5 days, or 500 mg three times a day for 3 days). A comparator group received quinine and doxycycline (Dx; 100 mg twice a day for 7 days). Study observation was 28 days per protocol. Sixty volunteers completed the study. Seven days of QDx cured 100% of the volunteers. One failure occurred in the lowest QAz regimen (on day 28) and none occurred in either of the two higher Az regimens. Cinchonism occurred in nearly all subjects. Overall, the azithromycin regimens were well tolerated, and no volunteers discontinued therapy. Three- and five-day azithromycin-quinine combination therapy appears safe, well tolerated, and effective in curing drug-resistant P. falciparum malaria. Further evaluation, especially in pediatric and obstetric populations, is warranted. From July 1989 to February 1990, 17 non-pregnant patients with severe falciparum malaria, aged 14 years and above received an initial intravenous quinine dihydrochloride loading dose of 20 mg/kg in 500 mls of normal saline or 5% dextrose infused over 4 hours followed by 100mg/kg infused 8 hourly for at least 24 hours. Sixteen comparable controls were similarly treated but without an initial loading dose. Oral quinine bisulfate 10mg/kg 8 hourly was substituted for a total of 7 days when patients were well enough. There was no significant difference in clinical and parasitological response between the two groups. Fever clearance time in hours was 44.00 +/- 13.92 (mean +/- SD) in the study group and 51.43 +/- 19.63 (mean +/- SD) in the control group (p > 0.05). Parasite clearance time in hours was 42.40 +/- 9.75 (mean +/- SD) in the study group and 47.05 +/- 7.69 (mean +/- SD) in the control group (p > 0.05). One patient from each group died. Mild toxic effects were common in both groups. Transient partial hearing loss occurred significantly more in the study than control group (p < 0.05). Hypoglycaemia during treatment occurred in 3 (18%) patients in the study group and 1 (6%) in the control group. The mean trough and peak plasma quinine levels in 3 patients per group was persistently higher than 9mg/L after first infusion. We conclude that though fairly well tolerated, quinine loading dose appears to have no advantage over the standard treatment for severe falciparum malaria at Kenyatta National Hospital, Nairobi, Kenya.
There is moderate quality evidence that quinine significantly reduces cramp frequency, intensity and cramp days in dosages between 200 and 500 mg/day. There is moderate quality evidence that with use up to 60 days, the incidence of serious adverse events is not significantly greater than for placebo in the identified trials. Further research is required on the optimal dose and duration of use, and also on alternative treatments.