Flagyl 400 MG Tablet: Uses, Side Effects, Dosages & Price

Flagyl 400 MG Tablet is used for the treatment and prevention of infections caused by anaerobic bacteria. Flagyl 400 MG Tablet works against the proliferation of a wide number of bacterial species in the body, most notably, Bacteroides, Clostridia, Fusobacteria, anaerobic cocci, Eubacteria, Gardnerella vaginalis, Entamoeba histolytica, Trichomonas, Giardia lamblia and Balantidium coli.

Flagyl 400 MG Tablet blocks the energy producing bacterial cells, thereby destroying the bacteria and parasites. It is manufactured by pharmaceutical brand, Abbott Health.

Flagyl 400 MG Tablet

Composition and Nature of Flagyl 400 MG Tablet:

The key salt that is present in the medicine is Metronidazole.

Uses of Flagyl 400 MG Tablet:

Flagyl 400 MG Tablet has multiple uses and it prevents bacterial infection of varying degrees.

It is given to a patient right after a surgery to prevent postoperative infections caused by anaerobic bacteria. Other than that it is used to treat general infections like blood infection, bone infection, pressure sores, genital tract infection or Urogenital trichomoniasis in both males and females, peptic ulcer disorder, infection of the brain, lungs, abdomen, gum and dental cavities, pelvis, intestines etc. It is also used to prevent amoebiasis and colitis associated with antibiotics.

Common Dosage of Flagyl 400 MG Tablet:

  • Post-operative treatment : In case of post-operative bacterial infection prevention, 400 mg of Flagyl 400 MG Tablet is given to the patient every 8 hours in the course of a day, right after operation. Initially it is administered intravenously which continues until the patient is able to administer it orally. In children, the dosage depends upon the body weight, and is 20-30 mg as per body weight, and is administered every 1-2 hours in children below 12 years. In case of infants 10 mg of Flagyl 400 MG Tablet is administered as per body weight. The frequency remains the same. In both the cases the Flagyl 400 MG Tablet is given before a surgery.
  • For general infections : The dosage (in milligrams), and the duration of the course depend on the severity and the type of infection. In most cases the course lasts for 7 days. In adults the dosage usually varies between 800 mg and 2000 mg. It is either given as a single dose every day or it might be divided into two to three doses in the course of a day. In children the dosage depends on the body weight. The thing that is kept in mind is that the dose should not exceed 2000 mg in the case of children on a daily basis. The dose among children between 1-13 years usually varies between 200 mg and 1000 mg.

How Flagyl 400 MG Tablet works?

Metronidazole is a class of nitroimidazole drugs. Metronidazole binds to the bacterial DNA covalently and interrupts the helical structure. Hence bacterial nucleic acid synthesis is prevented and the result is bacterial cell death.

Side effects of Flagyl 400 MG Tablet:

Every antibiotic has some mild side effects. But in some cases severe side effects can also develop. Talk to your doctor if the side effects persist or aggravate beyond normal measure.

Here are a few side effects of Flagyl 400 MG Tablet:

  • Nausea
  • Coated tongue
  • Headache
  • Gastrointestinal disorders
  • Metallic taste in the mouth
  • Muscle pain or joint pain
  • Diarrhea or loose motion
  • High temperature
  • Inflammation in the brain
  • Dark colored urine

Precautions and Warning When to Avoid Flagyl 400 MG Tablet:

Your doctor should know about all the pre-existing medical conditions that you have as well as the medicines that you take on a daily basis. Tell your doctor if you have allergies or if you are on any alternative medication. Some conditions that might make you more susceptible to the side effects of Flagyl 400 MG Tablet are alcoholism, seizures, muscle or joint pains caused by arthritis or any other disorder, and liver problems among others. Tell your doctor if you are scheduled for a surgery. Consultation is required in specific cases such as pregnancy, dermatitis, and, peripheral neuropathy.  Flagyl 400 MG Tablet should be administered orally.

Drug Interaction with Flagyl 400 MG Tablet:

You need to let the doctor know about all the medicines to avoid the occasion of drug interaction. Adverse drug interaction can lead to the development of complications or render the medicines ineffective (both Flagyl 400 and the other drug that you might be taking). Some of the drugs that are known to interact with Flagyl 400 MG Tablet are Phenytoin, Lithium, Phenorbarbital, Fluorouracil, Ciclosporin, Antimicrobials, Anticoagulants, Cimetidine. Alcohol consumption can also aggravate the side effects of Flagyl 400 MG Tablet.

Substitutes for Flagyl 400 MG Tablet:

Here are the medicines that can work as viable substitutes of Flagyl 400 MG Tablet:

  • Metron Forte 400 mg Tablet
  • Emnac 400 mg Tablet
  • Met 400 mg Tablet
  • Metgyl 400 mg Tablet
  • Sprot P 400 mg Tablet
  • Aldezol 400 mg Tablet
  • Aristogyl 400 mg Tablet


1) What is a parasitic infection?

Ans: Parasites are living organisms that depend on other beings and acquire nutrition from the host. Some of these parasites invade the body of the host and when this happens the host becomes ill This is called a parasitic infection. If not treated at the right time, parasitic infections can become life-threatening.

2) What will happen if I do not complete the course of the antibiotic?

Ans: Antibiotics work by targeting the bacterial DNA and prevent its proliferation systematically. This system gets disrupted when stopped abruptly before the course is finished. The bacteria or parasites are not destroyed completely, thereby making the body prone to another attack. And, the second time the infection spreads antibiotics proves to be less effective against these organisms.

3) Can I take birth control pills and Flagyl 400 MG Tablet together?

Ans: Flagyl 400 MG Tablet is not known to interrupt the action of birth control pills. But to be on the safe side the patient must consult a doctor.

4) Does Flagyl 400 affect menstruation?

Ans: Flagyl 400 MG Tablet is not known to cause any menstrual problems. It usually does not render periods irregular. However, if menstrual problems crop up after the consumption of Flagyl 400 MG Tablet, medical assistance must be sought immediately as it could be  due to an underlying medical condition.

5) What should I do if I forget a dose of Flagyl 400 MG Tablet?

Ans: If you forget a dose of Flagyl 400 MG Tablet, take the Flagyl 400 MG Tablet as soon as you remember. But if you remember when it is nearly time for the second dose, skip the dose. Do not take double doses.

Last updated on : 26-09-2019

Disclaimer : Docprime doesn’t endorse or take any guarantee of the accuracy or completeness of information provided under this article and these are the views strictly of the writer. Docprime shall not be held responsible for any aspect of healthcare services administered with the information provided on this article.

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