You should not use this medication if you are allergic to oxybutynin, or if you have untreated or uncontrolled narrow-angle glaucoma, a blockage in your digestive tract (stomach or intestines), or if you are unable to urinate.
Before using oxybutynin, tell your doctor if you have glaucoma, liver or kidney disease, an enlarged prostate, myasthenia gravis, ulcerative colitis, a blockage in your stomach or intestines, or a stomach disorder such as gastroesophageal reflux disease (GERD) or slow digestion.
Avoid becoming overheated or dehydrated during exercise and in hot weather. Oxybutynin can decrease perspiration and you may be more prone to heat stroke.
Oxybutynin can cause side effects that may impair your vision or reactions. Be careful if you drive or do anything that requires you to be alert and able to see clearly.
There are many other medicines that can interact with oxybutynin. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor. Keep a list with you of all the medicines you use and show this list to any doctor or other healthcare provider who treats you.
Stop using this medication and call your doctor if you have serious side effects such as hot and dry skin, extreme thirst, severe stomach pain or constipation, pain or burning when you urinate, or if you stop urinating.