Diarrhea, stomach upset, changes in taste, or nausea/vomiting may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly.
This medication may cause urine, sweat, saliva, or tears to turn brown-orange. This effect is harmless and will disappear when the medication is stopped. However, dentures and contact lenses may be permanently stained.
Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
Tell your doctor right away if any of these rare but serious side effects occur: easy bleeding/bruising, signs of a new infection (such as fever, persistent sore throat/cough), muscle weakness/pain, joint pain/swelling, eye pain/redness, vision problems, chest pain/pressure, persistent nausea/vomiting, unusual weakness/tiredness, dark urine, yellowing eyes/skin.
This medication may rarely cause a severe intestinal condition (Clostridium difficile-associated diarrhea) due to a type of resistant bacteria. This condition may occur during treatment or weeks to months after treatment has stopped. Do not use anti-diarrhea or opioid medications if you have any of the following symptoms because these products may make them worse. Tell your doctor right away if you develop: persistent diarrhea, abdominal or stomach pain/cramping, blood/mucus in your stool.
A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.
In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.
In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.