Hyoscyamine

Hyoscyamine is a chemical compound, a tropane alkaloid it is the levo-isomer to atropine. It is a secondary metabolite of some plants, particularly henbane (Hyoscamus niger.)

Brand names for hyoscyamine include Symax, Anaspaz, Buwecon, Cystospaz, Levsin, Levbid, Donnamar, NuLev, and Neoquess.

Additional recommended knowledge

Essential Laboratory Skills Guide

How to ensure accurate weighing results every day?

Correct Test Weight Handling Guide: 12 Practical Tips

Uses

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 end of life care.

Side effects

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, inappropriate affect, short-term memory loss and coma.

Pharmacology

Hyoscyamine is 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.

Isolation

Hyoscyamine can be extracted from plants of the Solanaceae family, notably Datura stramonium. Empirically it is C₁₇H₂₃NO₃. Its structural name is α-(hydroxymethyl)-, 8-methyl-8-azabicyclo[3.2.1]oct-3-yl ester, [3(S)-endo]-1αH,5αH-Tropan-3α-ol. Do not crush, chew, or divide the extended-release capsules

References

Drug Information Handbook 11th Ed. pp. 710-11. Lexi-Comp