Oxybutynin

Sounds like 'OX-i-BUE-ti-nin'

Oxybutynin is used to treat some bladder control problems. Find out how to take it safely and possible side effects. Oxybutynin is also called Ditropan.

What is oxybutynin?

Oxybutynin is used to treat some bladder control problems and urinary conditions such as overactive bladder, incontinence, urinary frequency (the need to pass urine/pee more often than usual) and urinary urgency (the need to pass urine more urgently than usual).

It works by relaxing the muscles in the bladder and in this way controls the release of urine and eases the symptoms. Read more about bladder control problems.

Dose

In New Zealand oxybutynin comes as tablets (5mg).

  • The usual dose of oxybutynin is 1 tablet two or three times a day.  
  • If you are older, your doctor may start you on a lower dose of 2.5 mg two times a day.
  • Always take your oxybutynin exactly as your doctor has told you. The pharmacy label on your medicine will tell you how much oxybutynin to take, how often to take it, and any special instructions.

How to take oxybutynin

  • Take oxybutynin tablets with a glass of water at the same times each day.
  • You can take oxybutynin with or without food.
  • If you need to cut a 5 mg tablet in half to get your dose, use a tablet cutter (which you can buy from a pharmacy) or talk to your pharmacist who may be able to halve them for you.
  • To reduce your urinary symptoms you must keep taking oxybutynin every day.
  • If you forget your dose, take it as soon as you remember that day. But if it is nearly time for your next dose, just take the next dose at the right time. Don't take double the dose.

Things to consider while you are taking oxybutynin 

Oxybutynin can impair your ability to do some tasks such as driving or using machines. Alcohol makes this worse. Avoid driving and doing other tasks or actions that need you to be alert until you see how this medicine affects you. Discuss your risk with your health professional.

Oxybutynin can interact with other medicines. Tell your doctor or pharmacist about all medicines you are taking including over the counter medicines, herbal and complementary medicines or recreational drugs. 

Possible side effects

Like all medicines, oxybutynin can cause unwanted side effects, although not everyone gets them. Often unwanted side effects improve as your body gets used to the new medicine.

Side effects What should I do?
  • Constipation
  • Stomach upset
  • Trouble peeing
  • Blurred vision
  • Dry eyes
  • These are quite common when you first start taking oxybutynin.
  • Read more for advice on managing constipation.
  • Try lubricating eye drops for dry eyes.
  • Tell your doctor if these bother you, your dose may need to be lowered.
  • Dry mouth
  • To prevent dry mouth, avoid using mouthwashes with alcohol.
  • Chewing on sugar-free gum, and drinking small sips of water as needed may also be helpful.
  • Keep good oral hygiene.
  • Tell your doctor if it bothers you. 
  • Read more about dry mouth.
  • Drowsiness, sleepiness or feeling tired
  
  • This is common when starting oxybutynin or after increasing the dose.
  • Be careful when driving or using tools until you know how this medicine affects you.
  • Feeling dizzy
  • This usually only happens when you start your medication. It should wear off in a few weeks.
  • Try not to stand up too quickly because you might fall.
  • If you feel dizzy, don't drive.
  • Headache
  • Tell your doctor. 
  • Confusion
  • Tell your doctor immediately or ring Healthline 0800 611 116.
For more information on side effects, see the Medsafe consumer information leaflets Apo-Oxybutynin.

Did you know that you can report a medicine side effect to the Centre for Adverse Reactions Monitoring (CARM)? Report a side effect to a product.

Learn more

The following links provide further information on oxybutynin. Be aware that websites from other countries may contain information that differs from New Zealand recommendations.

Oxybutynin NZ Formulary, NZ
Apo-Oxybutynin Medsafe Consumer Information Sheet, NZ
Oxybutynin Patient Info, UK

References

Oxybutynin  NZ Formulary, NZ
Apo–oxybutynin Medsafe, NZ
Oxybutynin – safe prescribing SaferRX, NZ

Additional resources for healthcare professionals

Urinary incontinence in adults BPAC, NZ, 2013
A practical guide to stopping medicines in older people BPAC, NZ, 2010
Polypharmacy in primary care – managing a clinical conundrum BPAC, NZ, 2014
Oxybutynin – safe prescribing – a little dry SafeRx, NZ

Credits: Sandra Ponen, Pharmacist.