Antispasmodic drugs relieve cramps or spasms of the stomach, intestines, and bladder. The drug described here, dicyclomine (Bentyl), is prescribed to treat a condition called irritable bowel syndrome. In some people, the main symptom is abdominal pain. In others, it is diarrhea or alternating bouts of diarrhea and constipation.

Dicyclomine is available only with a prescription and is sold as capsules, tablets (regular and extended-release forms), and syrup. The usual dosage for adults is 20 mg, four times a day. However, the physician may recommend starting at a lower dosage and gradually increasing the dose to reduce the chance of unwanted side effects. The dosage for children depends on the child's age. Check with the child's physician for the correct dosage.

Dicyclomine makes some people sweat less, which allows the body to overheat and may lead to heat prostration (fever and heat stroke). Anyone taking this drug...