In this drug factsheet:
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
- decreased sweating
- difficulty passing urine
- dry eyes
- dry mouth
- dry nose and throat
- loss of appetite
- skin redness or irritation (patch only)
- trouble sleeping
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:
- fast, uneven, or pounding heartbeat
- 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:
- antihistamines (e.g., cetirizine, doxylamine, diphenhydramine, hydroxyzine, loratadine)
- antipsychotics (e.g., chlorpromazine, clozapine, haloperidol, olanzapine, quetiapine, risperidone)
- "azole" antifungals (e.g., itraconazole, ketoconazole, voriconazole)
- barbiturates (e.g., butalbital, pentobarbital phenobarbital)
- benzodiazepines (e.g., alprazolam, diazepam, lorazepam)
- macrolide antibiotics (e.g., clarithromycin, erythromycin)
- muscle relaxants (e.g., cyclobenzaprine, methocarbamol, orphenadrine)
- narcotic pain relievers (e.g., codeine, fentanyl, morphine, oxycodone)
- potassium chloride
- seizure medications (e.g., carbamazepine, gabapentin, lamotrigine, phenytoin)
- thiazide diuretics (water pills; e.g., hydrochlorothiazide, indapamide, metolazone)
- 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.