Oxybutynin (patient information)

# Why is this medication prescribed
Oxybutynin is used to control urgent, frequent, or uncontrolled urination in people who have overactive bladder (a condition in which the bladder muscles have uncontrollable spasms), spina bifida (a disability that occurs when the spinal cord does not close properly before birth), or other conditions that affect the bladder muscles. Oxybutynin is in a class of medications called anticholinergics. It works by relaxing the bladder muscles to prevent urgent, frequent, or uncontrolled urination.

# How should this medicine be used
Oxybutynin comes as a tablet, a syrup, and an extended-release (long-acting) tablet to take by mouth. The tablets and syrup are usually taken two to four times a day. The extended-release tablet is usually taken once a day with or without food. Take oxybutynin at around the same time(s) every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take oxybutynin exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
Swallow the extended-release tablets whole with plenty of water or other liquid. Do not split, chew, or crush the extended-release tablets. Tell your doctor if you cannot swallow tablets.
Your doctor may start you on a low dose of oxybutynin and gradually increase your dose, not more than once every week.
Oxybutynin may control your symptoms, but will not cure your condition. Continue to take oxybutynin even if you feel well. Do not stop taking oxybutynin without talking to your doctor.
You may notice some improvement in your symptoms within the first two weeks of your treatment. However, it may take six to eight weeks to experience the full benefit of oxybutynin. Talk to your doctor if your symptoms do not improve at all within eight weeks.

# Other uses for this medicine
This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

# What special precautions should I follow
Before taking oxybutynin
- tell your doctor and pharmacist if you are allergic to oxybutynin or any other medications.
- tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: amiodarone (Cordarone, Pacerone); certain antibiotics such as clarithromycin (Biaxin), erythromycin (E.E.S., E-Mycin, Erythrocin), and tetracycline (Bristamycin, Sumycin, Tetrex); certain antifungals such as itraconazole (Sporanox),miconazole (Monistat), and ketoconazole (Nizoral); antihistamines; aspirin and other nonsteroidal anti-inflammatory medications (NSAIDS) such as ibuprofen (Advil, Motrin) and naproxen (Aleve, Naprosyn); cimetidine (Tagamet); diltiazem (Cardizem, Dilacor, Tiazac); fluvoxamine; ipratropium (Atrovent); iron supplements; certain medications for human immunodeficiency virus (HIV) such as indinavir (Crixivan), nelfinavir (Viracept), and ritonavir (Norvir, in Kaletra); medications for irritable bowel disease, motion sickness, Parkinson's disease, ulcers, or urinary problems; medications for osteoporosis (a condition in which bones are weak, fragile, and can break easily) such as alendronate (Fosamax), ibandronate (Boniva), and risedronate (Actonel); nefazodone; potassium supplements; quinidine; and verapamil (Calan, Covera, Isoptin, Verelan). Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
- tell your doctor if you have or have ever had benign prostatic hypertrophy (BPH; enlargement of the prostate, a male reproductive organ) or any other condition that makes it difficult for you to fully empty your bladder; any condition that prevents your stomach from emptying completely or slows the movement of food through your digestive system; or glaucoma (a serious eye condition that may cause loss of vision). Your doctor may tell you not to take oxybutynin. tell your doctor if you have or have ever had ulcerative colitis (sores in the intestine that cause stomach pain and diarrhea); gastroesophageal reflux disease (GERD; condition in which the contents of the stomach back up into the esophagus and cause pain and heartburn); hiatal hernia (condition in which a portion of the wall of the stomach bulges outward, and may cause pain and heartburn); hyperthyroidism (condition in which there is too much thyroid hormone in the body); myasthenia gravis (a disorder of the nervous system that causes muscle weakness); fast or irregular heartbeat; high blood pressure; or heart, liver, or kidney disease.
- tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking oxybutynin, call your doctor.
- if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking oxybutynin.
- you should know that this medication may make you drowsy or cause blurred vision. Do not drive a car or operate machinery until you know how this medication affects you.
- talk to your doctor about the safe use of alcohol while you are taking this medication. Alcohol can make the side effects from oxybutynin worse.
- you should know that oxybutynin may make it harder for your body to cool down when it gets very hot. Avoid exposure to extreme heat, and call your doctor or get emergency medical treatment if you have fever or other signs of heat stroke such as dizziness, nausea, headache, confusion, and fast pulse after you are exposed to heat.

# What special dietary instructions should I follow
Talk to your doctor about eating grapefruit and drinking grapefruit juice while taking this medicine.

# What should I do if I forget a dose
If you are taking the tablet or syrup, take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.
If you are taking the extended-release tablet and you remember more than eight hours before it is time for the next dose, take the missed dose right away. However, if your next dose is due in less than eight hours, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for the missed one.

# Side effects

## Mild side effects
Oxybutynin may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- dry mouth
- blurred vision
- dry eyes, nose, or skin
- stomach pain
- constipation
- diarrhea
- nausea
- heartburn
- gas
- change in ability to taste food
- headache
- dizziness
- weakness
- confusion
- sleepiness
- difficulty falling asleep or staying asleep
- nervousness
- flushing
- swelling of the hands, arms, feet, ankles, or lower legs
- back or joint pain
- frequent, urgent, or painful urination
- rash

## Severe side effects
If you experience the following symptom, call your doctor immediately:
- fast, irregular, or pounding heartbeat
If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online  or by phone .
Oxybutynin may cause other side effects. Call your doctor if you have any unusual problems while you are taking this medication.

# What storage conditions are needed for this medicine
Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom). Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.

# In case of emergency/overdose
In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.
Symptoms of overdose may include:
- restlessness
- uncontrollable shaking of a part of your body
- irritability
- seizures
- confusion
- hallucinations (seeing things or hearing voices that do not exist)
- flushing
- fever
- irregular heartbeat
- vomiting
- difficulty urinating
- slowed or difficult breathing
- inability to move
- coma (loss of consciousness for a period of time)
- memory loss
- agitation
- wide pupils (black circles in the centers of the eyes)
- dry skin

# What other information should I know
Keep all appointments with your doctor.
Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.
If you are taking the extended-release tablet, you may notice something that looks like a tablet in your stool. This is just the empty tablet shell and does not mean that you did not get your complete dose of medication.

# Brand names
- Ditropan
- Ditropan XL