| Indication | For treatment of bladder spasms, peptic ulcer disease, diverticulitis, colic, irritable bowel syndrome, cystitis, and pancreatitis. Also used to treat certain heart conditions, to control the symptoms of Parkinson's disease and rhinitis. |
| Pharmacodynamics | L-Hyoscyamine, the active optical isomer of atropine (dl-hyoscyamine), is a tertiary amine anticholinergic gastrointestinal agent. |
| Mechanism of action | Hyoscyamine competes favorably with acetylcholine for binding at muscarinic receptors in the salivary, bronchial, and sweat glands as well as in the eye, heart, and gastrointestinal tract. The actions of hyoscyamine result in a reduction in salivary, bronchial, gastric and sweat gland secretions, mydriasis, cycloplegia, change in heart rate, contraction of the bladder detrusor muscle and of the gastrointestinal smooth muscle, and decreased gastrointestinal motility. |
| Absorption | Absorbed totally and completely by sublingual administration as well as oral administration. |
| Volume of distribution | Not Available |
| Protein binding | 50% |
| Metabolism | Hepatic |
| Route of elimination | Not Available |
| Half life | 2-3.5 hours |
| Clearance | Not Available |
| Toxicity | Symptoms of overdose include headache, nausea, vomiting, blurred vision, dilated pupils, hot dry skin, dizziness, dryness of the mouth, difficulty in swallowing, and CNS stimulation. LD50=mg/kg(orally in rat) |