Dicycloverine, also known as dicyclomine, sold under the brand name Bentyl among others, is a medication that is used to treat spasms of the intestines such as those that occur in irritable bowel syndrome (IBS).

[7] It should not be given to children or infants with colic due to the risks of convulsions, difficult breathing, irritability, and restlessness,[9] and there is little evidence to support the efficacy in such use in any case.

[7] Dicycloverine can cause a range of anticholinergic side effects such as dry mouth, nausea, blurred vision, dizziness, confusion, severe constipation, stomach pain, heart palpitations, difficulty urinating, and seizures.

[13] It was included in the combination drug for morning sickness called Bendectin, along with doxylamine and vitamin B6 which was launched in the US in 1956; dicycloverine was removed from the formulation in 1976 after Merrell determined that it added no value.

Bendectin became the subject of many lawsuits due to allegations that it had caused birth defects similar to thalidomide, which Merrell had also marketed in the US and Canada.

[9] In 1994, the US Federal Trade Commission ordered Marion Merrell Dow, which had acquired Rugby Darby—the only generic manufacturer of dicycloverine in the US—to promise to grant licenses to its intellectual property on the drug to any company that wanted it, based on antitrust concerns.

The next year, Hoechst Marion Roussel, which by that time had acquired the business, granted a license to Endo Pharmaceuticals.