Oxybutynin

Oxybutynin, sold under the brand name Ditropan among others, is an anticholinergic medication primarily used to treat overactive bladder. It is widely considered a first-line therapy for overactive bladder due to its well-studied side effect profile, broad applicability, and continued efficacy over long periods of time. It works similar to tolterodine, darifenacin, and solifenacin, although it is usually preferred over these medications. It is sometimes used off-label for treatment of hyperhidrosis, or excessive sweating. It has also been used off-label to treat bedwetting in children, but this use has declined, as it is most likely ineffective in this role. It is taken by mouth or applied to the skin.

Common side effects include dry mouth, constipation, dizziness, trouble sleeping, and urinary tract infections. Serious side effects may include urinary retention and an increased risk of heat stroke. Use in pregnancy appears safe but has not been well studied while use in breastfeeding is of unclear safety. It is an antimuscarinic and works by blocking the effects of acetylcholine on smooth muscle.

Oxybutynin was approved for medical use in the US in 1975. It is available as a generic medication. In 2022, it was the 110th most commonly prescribed medication in the United States, with more than 5 million prescriptions.