The Web Health



Pronunciation: me-troe-NI-da-zole
Generic Name: Metronidazole (oral or injection)
Names of Brands: Flagyl, Flagyl ER, Flagyl I.V., RTU, Metro I.V., Protostat, Metryl
Dosage forms: Oral capsule (375 mg), oral suspension (100 mg/mL; 50 mg/mL),intravenous solution (500 mg/100 mL)… show all 5 dosage forms
Classes of Drugs: Amebicides, miscellaneous antibiotics

What Is Metronidazole?

Metronidazole is an antibiotic that helps treat infections caused by bacteria in the stomach, vagina, liver, skin joints, spinal cord, lungs, heart, or bloodstream.

Metronidazole can also be utilized for treating trichomoniasis, which is a sexually transmitted illness caused by parasites. The majority of sexual partners are treated simultaneously, even if one suffers no symptoms.Don't use metronidazole to treat any ailment that hasn't been evaluated by your physician.


It is not recommended to use metronidazole if you have recently consumed alcohol or taken disulfiram (Antabuse) within the last two weeks.

Don't drink alcohol or consume food or medications that contain propylene glycol when you are taking metronidazole for at least three days after the last day of taking it.

The presence of seizures and other nerve system disorders has been observed among patients receiving metronidazole. Stop using the drug immediately if you have any neurological symptoms like headaches, seizures, visual changes, weakness, numbness, or sensations of tingling.

This medication is not able to treat viral infections like the common flu or cold.

In studies on animals (mice or rats), the medicine was responsible for certain kinds of cancers or tumors. It is unclear if the effects are present for patients taking this medication. Consult your physician about the risks you face.

Before you Take this Drug

This medicine is for you if you're allergic to metronidazole (also known as secnidazole) or tinidazole, or if you suffer from any of the following conditions:

  • You've had a drink within the last three days.
  • You consumed food or other substances that contain propylene glycol within the past three days. You took medication or food that contains propylene glycol in the last three days.
  • You took disulfiram (Antabuse) in the last 14 days.

Could harm a baby who is not yet born. Don't use metronidazole to treat trichomoniasis in the initial trimester. Consult your physician when you are pregnant.

There are a few uses of metronidazole that have been approved for the treatment of adolescents and children. Metronidazole is not approved for treating vaginal infections among girls who have not yet begun their menstrual period.

To ensure you can safely take this medication, consult your physician, whether you've ever:

  • The liver condition;
  • Renal disease (or if you're taking dialysis);
  • A heart rhythm disorder
  • A stomach or intestinal illness like Crohn's disease;
  • A blood cell disorder, like anemia (lack of red blood cells) or low white blood cell (WBC) counts;
  • A fungal infection in any part of your body.
  • A nerve disorder.

Metronidazole has been linked to the development of cancer in animals. It's not yet known if this will occur in humans. Consult your physician about the potential risk.

It is not recommended to give birth within 24 hours after the use of metronidazole. If you use an infant pump at this time, you should throw away the milk and not give it to your infant.

Metronidazole warnings about breastfeeding and pregnancy (more details)

How to Take Metronidazole?

Use metronidazole as directed by your physician. Follow all instructions on the label of your prescription and study all medication guides or instruction sheets.

Metronidazole oral injections are administered by mouth. The injection is administered as an infusion into the veins. The healthcare professional will administer the injection in case you are incapable of taking the medicine by mouth.Shake your oral suspension (liquid). Use the measuring device supplied (not an ordinary spoon).Take your tablets with extended release in their entirety, but do not crush, chew, or break them.

If you're dealing with a vaginal infection, your partner might require metronidazole to ensure that you don't contract the same infection again.Metronidazole can be used for a period of up to 10 days in a row. You might need to repeat the dosage a few weeks later.Use this medication even if your symptoms rapidly get better. Inadequate doses can cause your illness to become more resistant to treatment. This medication will not help treat the symptoms of a viral illness (flu or a typical cold).

Metronidazole is not a treatment for the symptoms of a vaginal yeast infection. It is possible to develop the vaginal yeast infection again, which needs to be treated with antifungal medications. Inform your doctor if you are experiencing symptoms such as the appearance of discharge or itching during or following treatment with this drug.

Don't share this medication with anyone else, even if they suffer from similar symptoms as you do.This medication can alter the results of some medical tests. Inform any physician who treats patients that you're using this medication.Place it in a cool, dry place free of heat and moisture.

What Happens If I Miss a Dose?

You should take the medication as quickly as you can. However, avoid your missed dose if you are nearing the time to take the next dose. Don't take two doses at once.

What Happens If I Overdose?

Get medical attention in an emergency or contact the Poison Help line toll-free at 1-800-222-1222.

Overdose symptoms can consist of vomiting, numbness, burning sensations, or issues with balance or muscle movements.

What Should be Avoided?

When taking metronidazole and for the next 3 days following the previous dose Avoid drinking alcohol, consuming food and medicines, or using any other products that contain propylene glycol. You could experience unpleasant side effects such as headaches, nausea, stomach cramps, vomiting, and tingling or warmth on your face.

Side effects of Metronidazole

Seek medical attention immediately. If you are experiencing symptoms that indicate an allergy reaction (hives and itching, a warm sensation or tingling; fever; dry, dry vagina; stuffy nose; difficulty breathing; swelling of your throat or face) or an extreme skin reaction (fever and sore throat; burnt eyes; irritation; and red or purple skin itching, blistering, and peeling),



Prescription only

Pregnancy & Lactation

CSA Schedule*

Related Drugs
Related Stories