What side effects may I notice from receiving Metronidazole?

Side effects that you should report to your care team as soon as possible:
-Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat
-Dizziness, loss of balance or coordination, confusion or trouble speaking
-Fever, neck pain or stiffness, sensitivity to light, headache, nausea, vomiting, confusion, which may be signs of meningitis
-Heart rhythm changes—fast or irregular heartbeat, dizziness, feeling faint or lightheaded, chest pain, trouble breathing
-Liver injury—right upper belly pain, loss of appetite, nausea, light-colored stool, dark yellow or brown urine, yellowing skin or eyes, unusual weakness or fatigue
-Pain, tingling, or numbness in the hands or feet
-Redness, blistering, peeling, or loosening of the skin, including inside the mouth
-Seizures
-Severe diarrhea, fever
-Sudden eye pain or change in vision such as blurry vision, seeing halos around lights, vision loss
-Unusual vaginal discharge, itching, or odor
Side effects that usually do not require medical attention (report these to your care team if they continue or are bothersome):
-Headache
-Irritation at application site
-Nausea
-Stomach pain

This list may not describe all possible side effects for Metronidazole. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.