Flagyl is an antibiotic that is used to treat various bacterial infections. It alters the bacterial cell wall to restrict the bacterial growth. It is effective against parasitic infections as well. It is not effective against viral infections though such as common cold and flu. The chemical name of Flagyl is Metronidazole.


Flagyl is used to treat infections of the brain, bones, blood, stomach and intestines, and genital tract.

It prevents infections after surgery. Doctors prescribe it in dental ulcers and other dental infections. Infected leg ulcers and pressure sores are also treated by Flagyl.

If you’re on another medicinal therapy when your doctor prescribes Flagyl, discuss thoroughly with your doctor. The reason behind this precaution is the interaction of Flagyl with many other medicines.

It can interact with some cancer, epilepsy, leukemia and blood thinning medicines along with some medicines for alcoholism.


  • The adult dosage of Flagyl starts with an 800 mg tablet and then it is subsequently lowered down to 400 mg after every eight hours. The dose remains 400 mg after the second dose with the same interval of eight hours.
  • The dosage for children depends on the age and weight of the child.
  • The doctor prescribes flagyl every eight hours for children over eight weeks of age.
  • The children of age under eight weeks may be prescribed with flagyl after an interval of twelve hours.
  • Flagyl dosage before a surgery is different than a regular dose.
  • An adult should start taking flagyl 24 hours before the surgery schedule and keep taking 400 mg tablets with an interval of eight hours.
  • Post-surgery dosage may change form to an IV or suppository.
  • The children should start taking the prescribed Flagyl 1-2 hours before surgery.
  • The children’s dosage will be determined by the weight of the child.

Side Effects:

Flagyl may show some side effects in certain cases, but may not have any side effects with other patients.

The common side effects include numbness, tingling in the limbs, a distaste in the oral cavity, hearing loss (in some cases), fever, loss of appetite, nausea, vomiting, headache, stiffness of the neck and photosensitivity.

There’s a chance to develop a skin rash by taking Flagyl that occurs each time you take the drug.

Sometimes Flagyl can cause ringing in the ears and pain in the eyes but these side effects are not common.


  • Do not take Flagyl if you’re allergic to the medicine.
  • Seek immediate medical help if you experience a skin rash or swelling of the lips, tongue and throat; these are the characteristic signs of an allergic reaction to the medication.
  • Inform your doctor if you have a kidney or liver disease.
  • It should not be prescribed to patients of nervous system diseases.
  • Inform your doctor if you develop a stomach pain, loss of appetite, yellowing of the eyes and skin, fatigue or an altered stool pattern.
  • Storage precaution includes keeping it away from children under 30 degree centigrade temperature.