to younger people. This phenomenon is especially true for older people who are also on several other medications. Scopolamine use should be avoided in this age group because of these potent anticholinergic adverse effects, which have also been linked to an increased risk for dementia. Adverse effects Adverse effect incidence: Uncommon (0.1–1% incidence) adverse effects include: Dry mouth Anhidrosis (reduced ability to sweat to cool off) Tachycardia (usually occurs at higher doses and is succeeded by bradycardia) Bradycardia Urticaria (hives) Pruritus (itching) Rare (<0.1% incidence) adverse effects include: Constipation Urinary retention Hallucinations Agitation Confusion Restlessness Seizures Unknown frequency adverse effects include: Anaphylactic shock or reactions Dyspnea (shortness of breath) Rash Erythema Other hypersensitivity reactions Blurred vision Mydriasis (dilated pupils) Drowsiness Dizziness Somnolence Overdose Physostigmine, a cholinergic drug that readily crosses the blood–brain barrier, has been used as an antidote to treat the central nervous system depression symptoms of a scopolamine overdose. Other than this supportive treatment, gastric lavage and induced emesis (vomiting) are usually recommended as treatments for oral overdoses. The symptoms of overdose include: Tachycardia Arrhythmia Blurred vision Photophobia Urinary retention Drowsiness or paradoxical reaction, which can present with hallucinations Cheyne-Stokes respiration Dry mouth Skin reddening Inhibition of gastrointestinal motility Interactions Due to interactions with metabolism of other drugs, scopolamine can cause significant unwanted side effects or unpredictable synergies when taken with other medications or compounds. Specific attention should be paid to other medications in the same pharmacologic class as scopolamine, also known as anticholinergics. These additional compounds could also potentially interact with the metabolism of scopolamine: receptor-binding analgesic/pain medication such as gabapentinoids or opioids, ethanol, cannabinoids, zolpidem, thiazide diuretics, nicotine, benzodiazepines, buprenorphine, and especially anticholinergic drugs such as tiotropium, diphenhydramine, dimenhydrinate, etc. Nicotine in particular likely has a counteracting effect on the effects of scopolamine due to its opposing effect on acetylcholine signaling. Route of administration Scopolamine can be taken by mouth, subcutaneously, in the eye, and intravenously, as well as via a transdermal patch. Pharmacokinetic Scopolamine undergoes first-pass metabolism and about 2.6% is excreted unchanged in urine. Grapefruit juice decreases metabolism of scopolamine, consequently increasing plasma concentration. Pharmacodynamics The pharmacological effects of scopolamine are meditated through the drug’s competitive antagonism of the peripheral and central muscarinic acetylcholine receptors. Scopolamine acts as a nonspecific muscarinic antagonist at all four (M1, M2, M3, and M4) receptor sites. In doses higher than intended for medicinal use; the hallucinogenic alteration of