Oxybutynin

Key facts

• Oxybutynin is an anticholinergic that relaxes the bladder muscle, reducing sudden urges, leakage and frequent urination.
• It comes as tablets, extended-release tablets, a patch and a gel; effects on the bladder build over the first one to two weeks.
• Avoid oxybutynin if you have narrow-angle glaucoma or difficulty emptying your bladder; by relaxing muscle it can raise eye pressure or cause urinary retention.
• Seek urgent care for severe abdominal pain, inability to pass urine, or eye pain with blurred vision and halos around lights.

What oxybutynin treats

Oxybutynin treats overactive bladder, including urinary urgency, frequency and urge incontinence, and neurogenic bladder from conditions such as spinal cord injury or spina bifida. It reduces how often you need to urinate and how often leakage happens.

How oxybutynin works

The bladder empties when a nerve chemical, acetylcholine, tells its muscular wall to contract. Oxybutynin blocks the receptors acetylcholine acts on, so the bladder muscle contracts less often and can hold more urine before you feel the urge to go.

Before you take it

• Do not take oxybutynin if you have narrow-angle glaucoma, a blocked bladder or gut, or a condition that severely slows digestion, such as paralytic ileus.
• Tell your prescriber about any heart rhythm problems, myasthenia gravis, or liver or kidney disease.
• Other anticholinergic medicines, including some antihistamines, antidepressants and antipsychotics, add to the drying and cognitive side effects; combining several raises the risk of confusion, especially in older adults.
• Oxybutynin reduces sweating; take extra care to avoid overheating in hot weather or during intense exercise, since heat-related illness risk rises.

Side effects

Common effects include dry mouth, constipation, blurred vision and drowsiness.

Seek urgent medical care for:

• Inability to urinate or severe lower abdominal pain.
• Eye pain, halos around lights, or sudden vision changes.
• A fast or irregular heartbeat.
• Confusion, agitation, or hallucinations, particularly in older adults.
• Fever with hot, dry skin and no sweating.

Safety essentials

• Oxybutynin is contraindicated in narrow-angle glaucoma and in urinary or gastric retention, since both can worsen quickly; confirm neither applies before starting.
• Older adults are more sensitive to anticholinergic side effects, including confusion and falls; treatment often starts at a lower dose.
• Stay well hydrated and avoid excessive heat exposure, since reduced sweating raises the risk of heat-related illness.

This page is educational and does not replace advice from a doctor or pharmacist who knows your health history.