Dizziness, headache, diarrhea, nausea, stomach pain, loss of appetite, constipation, changes in taste, and dry mouth may occur. If any of these effects persist or worsen, notify your doctor or pharmacist promptly.
This drug may cause urine to darken in color. This is harmless.
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 immediately if any of these unlikely but serious side effects occur: unsteadiness, seizures, mental/mood changes, numbness/tingling of hands/feet, painful urination.
Tell your doctor immediately if any of these rare but very serious side effects occur: sore throat, persistent fever, unusual bleeding/bruising, severe stomach pain, persistent nausea/vomiting.
This medication may be used to treat a severe intestinal condition (pseudomembranous colitis) due to a type of resistant bacteria. However, sometimes treatment with metronidazole may fail. Tell your doctor immediately if you develop: persistent diarrhea, abdominal or stomach pain/cramping, or blood/mucus in your stool. This condition may occur weeks after treatment with other antibiotics has stopped. Do not use anti-diarrhea products or narcotic pain medications if you have any of these symptoms because these products may make them worse.
Use of this medication for prolonged or repeated periods may result in oral thrush or a new vaginal yeast infection (oral or vaginal fungal infection). Contact your doctor if you notice white patches in your mouth, a change in vaginal discharge, or other new symptoms.
A very serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction may include: rash, itching, swelling, 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.