How does this medication work? What will it do for me?

Oxybutynin belongs to the family of medications called anticholinergics. It is also an antispasmodic. Oxybutynin is used to relieve symptoms associated with an overactive bladder, such as urinary urgency (a need to urinate right away), urinary frequency, leakage, or urge incontinence (leaking or wetting caused by an unstoppable urge to urinate).

This medication works by relaxing the muscles in the bladder. It helps to reduce bladder spasms, the urge to pass urine, and the frequency of urination.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

What form(s) does this medication come in?

Each patch imprinted with "OXYTROL 3.9" contains 36 mg of oxybutynin. The patch is composed of three layers. Layer 1 (the backing film) is a thin flexible polyester/ethylene-vinyl acetate film that makes the patch stronger and protects the sticky medication layer. Layer 2 (the sticky medication layer) is a cast film of acrylic adhesive containing oxybutynin and triacetin. Layer 3 (the release liner) is two overlapped siliconized polyester strips that are peeled off and discarded prior to applying the patch.

How should I use this medication?

The oxybutynin skin patch delivers medication slowly and constantly through the skin and into the bloodstream over a 3- to 4-day period. A new patch is applied every 3 to 4 days (twice a week).

The patch should be applied to clean, dry, and smooth skin on the abdomen (stomach area), hips, or buttocks. Avoid the waistline area, since tight clothing may rub against the patch. The area of skin where the patch is applied should not be oily, irritated, cut, scraped, or have other skin problems. When applying a new patch, use a different area of skin from the most recent patch site. Do not use the same area for the patch for at least 1 week. Once a patch is removed from its protective pouch, apply it right away.

To apply the patch:

  1. Remove the first piece of protective liner.
  2. Place the patch, adhesive face down, firmly on the skin.
  3. Bend the patch in half and gently roll the remaining part onto the skin using the tips of the fingers. As the patch is rolled in place, the second piece of the protective liner should move off the patch.
  4. Apply firm pressure over the surface of the patch to make sure the patch stays on.

Contact with water while bathing, swimming, showering, or exercising will not change the way that the patch works.

If the patch partly or completely falls off, press it back in place. If the patch does not stay on, throw it away. You should then put on a new patch in a different area, but continue to follow your original application schedule. If you forget to change your patch after 3 or 4 days, remove the old patch, put on a new patch in a different area, and continue to follow your original application schedule.

Since a removed patch will still contain some oxybutynin, throw it away so that it cannot be accidentally worn or swallowed by another person (especially a child) or a pet.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are using the medication without consulting your doctor.

Store this medication at room temperature, protect it from light and moisture, and keep it out of the reach of children.

Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.

Who should NOT take this medication?

Do not use oxybutynin if you:

  • are allergic to oxybutynin or any ingredients of the medication, including the adhesive material (in the patch form)
  • have acute blood loss that compromises the heart or circulation
  • have intestinal atony (loss of tone of intestinal muscles) due to aging or debilitation
  • have intestinal obstruction
  • have megacolon (dilated large intestine) or toxic megacolon as a complication of ulcerative colitis
  • have severe colitis (inflammation of the gastrointestinal tract)
  • have myasthenia gravis
  • have obstructive uropathy (blocked urine flow)
  • have partial or complete obstruction of the gastrointestinal tract or are at risk for this condition
  • have uncontrolled narrow-angle glaucoma or are at risk for this condition
  • have urinary retention or obstruction or are at risk for these conditions

What side effects are possible with this medication?

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent. The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

  • abdominal bloating or gas
  • abdominal pain
  • blurred vision
  • constipation
  • decreased sweating
  • difficulty passing urine
  • drowsiness
  • dry eyes
  • dry mouth
  • dry nose and throat
  • fever
  • flushing
  • headache
  • loss of appetite
  • nausea
  • rash
  • skin redness or irritation (patch only)
  • trouble sleeping
  • vomiting

Although most of these side effects listed below don't happen very often, they could lead to serious problems if you do not check with your doctor or seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

  • diarrhea
  • fast, uneven, or pounding heartbeat
  • hallucinations
  • mood changes
  • unusual tiredness or weakness

Stop taking the medication and seek immediate medical attention if any of the following occur:

  • signs of a serious allergic reaction (swelling of face or throat, hives, or difficulty breathing)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Are there any other precautions or warnings for this medication?

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Bladder obstruction: If you have significant bladder outflow obstruction, your doctor should closely monitor your condition while taking oxybutynin. Report any change in your urinary or bladder habits to your doctor.

Body temperature: Oxybutynin causes a decrease in sweating, which is one of the body's ways of cooling off. When oxybutynin is taken during very hot weather, it can cause fever and heat stroke due to the body being unable to cool down enough. Take care not to overheat when you are taking this medication. Stay in a cool environment if possible, limit the length of time you spend outdoors, and drink plenty of water to reduce the risk of heat stroke.

Dental problems: Long-term use of oxybutynin may reduce saliva, which can lead to dental problems such as cavities, gingivitis, and discomfort. You should see your dentist regularly and let your dentist know about this and any other medications you may be taking.

Drowsiness/reduced alertness: Oxybutynin may cause drowsiness or blurred vision. Avoid activities requiring mental alertness, such as driving, operating machinery, or performing hazardous work, until you know how this medication affects you. Alcohol and other medications that cause drowsiness may increase the drowsiness caused by oxybutynin.

Gastrointestinal disorders: If you have an obstructive gastrointestinal disorder, ulcerative colitis, or gastroesophageal reflux, your doctor should closely monitor your condition while taking oxybutynin.

Heart conditions: The symptoms of heart disease, heart failure, abnormal heart rhythms, and high blood pressure can be aggravated by oxybutynin. If you have any of these conditions, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Prostate enlargement: The symptoms of prostate enlargement may be made worse by oxybutynin. If you have prostate enlargement or another problem involving the prostate gland, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Thyroid problems: The symptoms of overactive thyroid may be worsened by oxybutynin. If you have an overactive thyroid, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Pregnancy: The safety of oxybutynin for use during pregnancy has not been established. This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately.

Breast-feeding: It is not known if oxybutynin passes into breast milk. If you are a breast-feeding mother and are taking this medication, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of using this medication have not been established for children under 5 years old.

What other drugs could interact with this medication?

There may be an interaction between oxybutynin and any of the following:

  • alcohol
  • aclinidium
  • antihistamines (e.g., cetirizine, doxylamine, diphenhydramine, hydroxyzine, loratadine)
  • antipsychotics (e.g., chlorpromazine, clozapine, haloperidol, olanzapine, quetiapine, risperidone)
  • aripiprazole
  • atropine
  • azelastine
  • "azole" antifungals (e.g., itraconazole, ketoconazole, voriconazole)
  • barbiturates (e.g., butalbital, pentobarbital phenobarbital)
  • belladonna
  • benztropine
  • benzodiazepines (e.g., alprazolam, diazepam, lorazepam)
  • cyclobenzaprine
  • disopyramide
  • donepezil
  • flavoxate
  • galantamine
  • glycopyrrolate
  • ipratropium
  • ketotifen
  • macrolide antibiotics (e.g., clarithromycin, erythromycin)
  • mirabegron
  • muscle relaxants (e.g., cyclobenzaprine, methocarbamol, orphenadrine)
  • nabilone
  • narcotic pain relievers (e.g., codeine, fentanyl, morphine, oxycodone)
  • pimozide
  • potassium chloride
  • rivastigmine
  • scopolamine
  • seizure medications (e.g., carbamazepine, gabapentin, lamotrigine, phenytoin)
  • thiazide diuretics (water pills; e.g., hydrochlorothiazide, indapamide, metolazone)
  • tiotropium
  • tolterodine
  • topiramate
  • tranylcypromine
  • tricyclic antidepressasnts (e.g., amitriptyline, clomipramine, desipramine, trimipramine)

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

  • stop taking one of the medications,
  • change one of the medications to another,
  • change how you are taking one or both of the medications, or
  • leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.