Metronidazole is used to treat acne rosacea (adult acne), a chronic condition in which the facial skin is inflamed and sores develop. Metronidazole decreases the redness and number of sores but may not be a cure. It is also used to treat some vaginal infections.
This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.
Metronidazole comes as a cream, lotion, or gel to be applied to your skin and as a gel to be used in the vagina. Metronidazole usually is used once or twice a day. It is used twice daily for 5 consecutive days to treat vaginal infections. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Use metronidazole exactly as directed. Do not use more or less of it or use it more often than prescribed by your doctor.
If you are using metronidazole to treat acne, your symptoms probably will improve within 3 weeks and continue to improve over the following 6 weeks or more. Continue to use metronidazole. Do not stop using metronidazole without talking to your doctor. Your symptoms may worsen when you stop the drug.
For acne, wash the affected skin area with mild soap about 15-20 minutes before applying the medication. Apply a thin layer of cream, lotion, or gel and rub it gently into the affected area. Do not allow the gel to get into your eyes. You may then apply a moisturizer (if your skin is dry) and cosmetics. Ask your doctor for advice on what cosmetics to use.
Metronidazole gel for the vagina comes with a special applicator. Read the instructions provided with it and follow these steps:
- Fill the special applicator that comes with the gel to the level indicated.
- Lie on your back with your knees drawn upward and spread apart.
- Gently insert the applicator into your vagina and push the plunger to release the medication.
- Withdraw the applicator and wash it with soap and warm water.
- Wash your hands promptly to avoid spreading the infection.
The dose should be applied when you lie down to go to bed. The drug works best if you do not get up again after applying the drug except to wash your hands and the applicator. You may wish to wear a sanitary napkin while using the vaginal gel to protect your clothing against stains. Do not use a tampon because it will absorb the drug. While using this drug, do not douche because it will wash the drug out of the vagina and decrease its effectiveness. Continue using this drug even if you get your period during the time of treatment.
Before using metronidazole,
- tell your doctor and pharmacist if you are allergic to metronidazole or any other drugs.
- tell your doctor and pharmacist what prescription and nonprescription medications you are taking, especially anticoagulants ('blood thinners') such as warfarin (Coumadin) and vitamins.
- tell your doctor if you have or have ever had a central nervous system disease, liver or blood disease, or Crohn's disease.
- tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while using metronidazole, call your doctor.
- plan to avoid unnecessary or prolonged exposure to sunlight and to wear protective clothing, sunglasses, and sunscreen. Metronidazole may make your skin sensitive to sunlight.
Do not drink alcohol while using the vaginal gel. Alcohol may cause an upset stomach, vomiting, stomach cramps, headaches, sweating, and flushing (redness of the face).
Apply the acne cream, lotion, or gel as soon as you remember but do not apply a double dose to make up for a missed dose.
Apply the vaginal gel the next morning or night and continue with your usual dosing schedule.
Metronidazole may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- increased skin redness, dryness, burning, irritation, or stinging
If you experience any of the following symptoms while using the vaginal gel, call your doctor immediately:
- stomach pain
- foul-smelling vaginal discharge
If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online [at Web Site] or by phone [1-800-332-1088].
Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom). Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.
Keep all appointments with your doctor. Metronidazole is for external use only. Do not let metronidazole get into your eyes, nose, or mouth, and do not swallow it. Do not apply dressings, bandages, cosmetics, lotions, or other skin medications to the area being treated unless your doctor tells you.
Do not have sexual intercourse during the 5 days that you use the vaginal gel.
Do not let anyone else use your medication. Ask your pharmacist any questions you have about refilling your prescription.
If you still have symptoms of infection after you finish the metronidazole, call your doctor.
It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.
AHFS® Consumer Medication Information. © Copyright, The American Society of Health-System Pharmacists, Inc., 7272 Wisconsin Avenue, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.
Last Reviewed: September 1, 2010.