Brand Name(s):

  • Flagyl®
  • Flagyl I.V.®
  • Flagyl®I.V. RTU®

IMPORTANT WARNING

Metronidazole can cause cancer in laboratory animals. Talk to your doctor about the risks and benefits of using this medication.

WHY is this medicine prescribed?

Your doctor has ordered metronidazole, an antibiotic, to help treat your infection. The drug will be added to an intravenous fluid that will drip through a needle or catheter placed in your vein for 1 hour, three or four times a day.

Metronidazole eliminates bacteria that cause many infections, including meningitis; pneumonia; and stomach, skin, bone, joint, heart, and gynecological infections. This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

Your health care provider (doctor, nurse, or pharmacist) may measure the effectiveness and side effects of your treatment using laboratory tests and physical examinations. It is important to keep all appointments with your doctor and the laboratory. The length of treatment depends on how your infection and symptoms respond to the medication.

What SPECIAL PRECAUTIONS should I follow?

Before administering 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), astemizole (Hismanal), disulfiram (Antabuse), lithium (Lithobid), phenobarbital, phenytoin (Dilantin), and vitamins.
  • tell your doctor if you have or have ever had blood, kidney, or liver 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 taking metronidazole, call your doctor.
  • remember you should not drink alcoholic beverages while taking metronidazole. Alcohol may cause an upset stomach, vomiting, abdominal cramps, headache, sweating, and flushing (redness of the face).
  • 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.

HOW should this medicine be used?

Before you administer metronidazole, look at the solution closely. It should be clear and free of floating material. Gently squeeze the bag or observe the solution container to make sure there are no leaks. Do not use the solution if it is discolored, if it contains particles, or if the bag or container leaks. Use a new solution, but show the damaged one to your health care provider.

It is important that you use your medication exactly as directed. Do not stop your therapy on your own for any reason because your infection could worsen and result in hospitalization. Do not change your dosing schedule without talking to your health care provider. Your health care provider may tell you to stop your infusion if you have a mechanical problem (such as a blockage in the tubing, needle, or catheter); if you have to stop an infusion, call your health care provider immediately so your therapy can continue.

What SIDE EFFECTS can this medicine cause?

Metronidazole may cause side effects. Tell your health care provider if any of these symptoms are severe or do not go away:

  • vomiting
  • upset stomach
  • diarrhea
  • loss of appetite
  • dry mouth or sharp, unpleasant metallic taste
  • dark or reddish-brown urine
  • furry tongue or mouth or tongue irritation
  • numbness or tingling of the hands or feet

If you experience any of the following symptoms, call your health care provider immediately:

  • rash
  • itching
  • stuffy nose
  • fever
  • joint pain

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].

What should I know about STORAGE and DISPOSAL of this medication?

  • Your health care provider probably will give you a several-day supply of metronidazole at a time. You will be told to store it at room temperature and protect it from direct light.

Store your medication only as directed. Make sure you understand what you need to store your medication properly.

Keep your supplies in a clean, dry place when you are not using them, and keep all medications and supplies out of reach of children. Your health care provider will tell you how to throw away used needles, syringes, tubing, and containers to avoid accidental injury.

What should I do in case of OVERDOSE?

In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.

If you are receiving metronidazole in your vein or under your skin, you need to know the symptoms of a catheter-related infection (an infection where the needle enters your vein or skin). If you experience any of these effects near your intravenous catheter, tell your health care provider as soon as possible:

  • tenderness
  • warmth
  • irritation
  • drainage
  • redness
  • swelling
  • pain

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.