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Medications and Drugs

Brand Names: Flagyl, Flagyl 375, Flagyl ER

Generic Name: metronidazole (Pronunciation: me troe NI da zole)

What is metronidazole (Flagyl, Flagyl 375, Flagyl ER)?

Metronidazole is an antibiotic. It fights bacteria in your body.

Metronidazole is used to treat bacterial infections of the vagina, stomach, skin, joints, and respiratory tract. This medication will not treat a vaginal yeast infection.

Metronidazole may also be used for purposes not listed in this medication guide.

Flagyl 375 mg

capsule, gray/green, imprinted with FLAGYL, 375mg

Flagyl 500 mg

oblong, blue, imprinted with 500, FLAGYL

Flagyl ER 750 mg

elliptical, blue, imprinted with SEARLE 1961, FLAGYL ER

Metronidazole 250 mg-DAN

round, white, imprinted with DAN, 5540

Metronidazole 250 mg-MUT

round, white, imprinted with MP 45

Metronidazole 250 mg-SID

round, white, imprinted with SL 333

Metronidazole 250 mg-TEV

round, white, imprinted with 93, 851

Metronidazole 250 mg-WAT

round, white, imprinted with 5540, DAN

Metronidazole 500 mg-MUT

oval, white, imprinted with MP 46

Metronidazole 500 mg-SCH

round, white, imprinted with 5552, DAN DAN

Metronidazole 500 mg-TEV

oblong, white, imprinted with 93 93, 852

Metronidazole 500 mg-WAT

round, white, imprinted with 5552, DAN DAN

Metronidazole 500mg-SID

oblong, white, imprinted with SL 334

What are the possible side effects of metronidazole (Flagyl, Flagyl 375, Flagyl ER)?

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have any of these serious side effects:

  • numbness or tingling in your hands or feet;
  • white patches or sores inside your mouth or on your lips;
  • pain or burning when you urinate;
  • diarrhea that is watery or bloody;
  • vision problems, pain behind your eyes;
  • trouble concentrating, slurred speech, mood or behavior changes, tremors, muscle twitching, seizure (convulsions);
  • fever, chills, muscle pain, confusion, headache, sore throat, neck stiffness, increased sensitivity to light, drowsiness, nausea and vomiting; or
  • severe skin reaction -- fever, sore throat, swelling in your face or tongue, burning in your eyes, skin pain, followed by a red or purple skin rash that spreads (especially in the face or upper body) and causes blistering and peeling.

Less serious side effects may include:

  • stomach pain, diarrhea;
  • dizziness, loss of balance;
  • vaginal itching or discharge;
  • dry mouth or unpleasant metallic taste;
  • cough, sneezing, runny or stuffy nose; or
  • swollen or sore tongue.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What is the most important information I should know about metronidazole (Flagyl, Flagyl 375, Flagyl ER)?

Take this medication for the full prescribed length of time. Your symptoms may improve before the infection is completely cleared. Skipping doses may also increase your risk of further infection that is resistant to antibiotics. Metronidazole will not treat a viral infection such as the common cold or flu.

Do not drink alcohol while you are taking metronidazole and for at least 3 days after you stop taking it. You may have unpleasant side effects such as fast heartbeats, warmth or redness under your skin, tingly feeling, nausea, and vomiting.

Report Problems to the Food and Drug Administration

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

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