Generic Flagyl

Common use

Flagyl is an antibiotic used against anaerobic bacteria Peptostreptococcus, Clostridium sp., Bacteroides sp., Prevotella, Fusobacterium, Veillonella and certain parasites such as Trichomonas vaginalis (vaginitis), Giardia intestinalis (lambliosis of bowels and liver), Entamoeba histolytica. This medication is used to treat such conditions: bacterial peritonitis, liver abscesses, abscesses of the ovaries and the Fallopian tubes.



Dosage and directions

Your dose should be administered by your physician depending on your condition, disease and age. Flagyl may be taken orally with or without food. In the hospital sometimes, Flagyl is prescribed intravenously to treat serious infections. Take the extended-release tabs of Flagyl at least 1-2 hours before or after a meal (on an empty stomach). Do not chew, break or crush extended-release tabs and swallow them whole. Do not stop to take this drug even if you feel fine and your symptoms disappeared unless your doctor recommended it.



Precautions

Long treatment requires complete blood count on a regular basis. Avoid drinking alcohol. Intake of Flagyl in patients is not advised during first trimester of pregnancy. Let your doctor know if you are pregnant or plan to become pregnant, have liver disease, a stomach or intestinal disease such as Crohn's disease, a blood cell disorder such as anemia or leukopenia, epilepsy or other seizure and nerve disorders.



Contraindications

Hypersensitivity.



Possible side effect

Nausea, taste of metal in mouth, anorexia, abdominal pain, vomit, diarrhea, headache, dizzying, allergy (rash, hives), leucopenia and brown-red color of urine in patients treated for long time with this medication. Serious side effects include seizures and damage of nerves resulting in numbness and tingling of extremities, if you experience this you need immediate help of your doctor.



Drug interaction

Flagyl is compatible with sulphanilamides and antibiotics. Its combination with disulphiram, indirectly-acting inhibitors of clotting and certain myorelaxants is not desired. Non compatible with alcoholic beverages. Flagyl increases levels of lithium in blood serum. Flagyl should not be co-administered with amprenavir for treating human immunodeficiency disease.



Missed dose

If you missed a dose take it as soon as you remember. If it almost time of your next dose just skip it and return to your regular schedule. Never double dose this medication.



Overdose

In case of serious and persistent nausea, vomiting, dizziness, loss of balance or coordination, numbness and tingling, or seizures consult your doctor about medical attention.



Storage

Store at room temperature between 59-77 degrees F (15-25 degrees C) away from light and moisture, kids and pets. Do not use after expiration term.



Disclaimer

We provide only general information about medications which does not cover all directions, possible drug integrations, or precautions. Information at the site cannot be used for self-treatment and self-diagnosis. Any specific instructions for a particular patient should be agreed with your health care adviser or doctor in charge of the case. We disclaim reliability of this information and mistakes it could contain. We are not responsible for any direct, indirect, special or other indirect damage as a result of any use of the information on this site and also for consequences of self-treatment.

Clinical Verification

Last Clinically Updated: August 15, 2026

Written By

Dr. Elena Vance, PharmD

Clinical Specialist in Neuropharmacology

Fact Checked By

Marcus Thorne, MS

Biomedical Data & FDA Label Verification

Medically Reviewed By

Dr. Arthur Campbell, MD

Board-Certified Psychiatrist (ABPN)