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Product description Safety information Side Effects

Drug Name

Flagyl ER (Metronidazole)

Drug Uses

Flagyl ER is an antibiotic. It fights bacteria in your body. Flagyl ER is used to treat bacterial infections of the vagina, stomach, skin, joints, and respiratory tract. This medication will not treat a vaginal yeast infection. Flagyl ER may also be used for purposes other than those listed in this medication guide.

How to use

Use Flagyl ER as directed by your doctor. Check the label on the medicine for exact dosing instructions.

Take Flagyl ER by mouth on an empty stomach at least 1 hour before or 2 hours after eating.

Swallow Flagyl ER whole. Do not break, crush, or chew before swallowing.

To clear up your infection completely, take Flagyl ER for the full course of treatment. Keep taking it even if you feel better in a few days.

If you miss a dose of Flagyl ER, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once.

Ask your health care provider any questions you may have about how to use Flagyl ER.

Drug Class and Mechanism

Flagyl ER is an oral antiprotozoal and antibacterial. It is thought to work by entering the bacterial cell, acting on some components of the cell and destroying the bacteria.

Missed Dose

Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and take the medicine at your next regularly scheduled time. Do not take extra medicine to make up the missed dose.

Storage

Flagyl ER should be stored at room temperature and protected from light.

Warnings/Precautions

Do NOT use Flagyl ER E if:

• you are allergic to any ingredient in Flagyl ER or to other nitroimidazoles (eg, tinidazole)
• you are in the first 3 months of pregnancy
• you are taking busulfan, an ergot alkaloid (eg, ergotamine), or you have taken disulfiram within the past 2 weeks
• you are taking an HIV protease inhibitor that contains alcohol (eg, amprenavir solution); check with your pharmacist if you are unsure if the medicine contains alcohol you drink alcohol

Contact your doctor or health care provider right away if any of these apply to you.

Some medical conditions may interact with Flagyl ER. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:

• if you are pregnant, planning to become pregnant, or are breast-feeding
• if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
• if you have allergies to medicines, foods, or other substances
• if you have nerve, brain, or blood problems; Crohn disease; or a history of liver problems

Some MEDICINES MAY INTERACT with Flagyl ER. Tell your health care provider if you are taking any other medicines, especially any of the following:

• Barbiturates (eg, phenobarbital) or phenytoin because they may decrease Flagyl ER's effectiveness
• Anticoagulants (eg, warfarin), busulfan, ergot alkaloids (eg, ergotamine), HIV protease inhibitors containing alcohol (eg, amprenavir solution), lithium, or macrolide immunosuppressants (eg, tacrolimus) because the risk of their side effects may be increased by Flagyl ER
• Disulfiram because side effects, such as mental or mood changes, may occur
• Oral contraceptives (eg, birth control pills) because their effectiveness may be decreased by Flagyl ER Extended-Release Tablets

Possible Side Effects

All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:

• Appetite loss; constipation; diarrhea; dizziness; headache; metallic taste; nausea; stomach upset; vomiting.

Seek medical attention right away if any of these SEVERE side effects occur:

• Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); bloody stools; increased or decreased urination; numbness, tingling, or burning of your arms, hands, legs, or feet; seizures; severe diarrhea; sore throat, chills, or fever; stomach pain or cramps; vaginal itching, odor, or discharge; white patches in the mouth.

More Information

If you have any questions about Casodex, please talk with your doctor, pharmacist, or other health care provider.

Casodex is to be used only by the patient for whom it is prescribed. Do not share it with other people.

If your symptoms do not improve or if they become worse, check with your doctor.