Overview:
Hyoscyamine is a tropane alkaloid. It is the levorotary isomer to atropine. It is found in certain plants of the Solanaceae family, including belladonna, brugmansia, henbane, mandrake, and datura. Hyoscyamine is an anticholinergic, specifically an antimuscarinic, working by blocking the action of acetylcholine at parasympathetic sites in smooth muscle, secretory glands and the CNS; increases cardiac output, dries secretions, and antagonizes serotonin. At comparable doses, hyoscyamine has 98 per cent of the anticholinergic power of atropine, while scopolamine has 92 per cent of the antimuscarinic potency of atropine.
Brand names for hyoscyamine include Symax, HyoMax, Anaspaz, Buwecon, Cystospaz, Levsin, Levbid, Donnamar, NuLev, Buscopan (containing the derivative hyoscine-N-butylbromide), Hyospasmol (also hyoscine-N-butylbromide) and Neoquess.
Hyoscyamine is used to provide symptomatic relief to various gastrointestinal disorders including spasms, peptic ulcers, irritable bowel syndrome, pancreatitis, colic and cystitis. It has also been used to relieve some heart problems, control some of the symptoms of Parkinson's disease, as well as for control of respiratory secretions in palliative care.
Side Effects and Adverse Reactions:
Side effects include dry mouth and throat, eye pain, blurred vision, restlessness, dizziness, arrythmia, flushing, faintness. An overdose will cause headache, nausea, vomiting and CNS symptoms including disorientation, hallucinations, euphoria, sexual arousal, short-term memory loss, and possible coma in extreme cases.
Research:
