Generic Name: Metronidazole Tablets and Capsules (MET roe NYE da zole)
Brand Name: Flagyl
Medically reviewed on September 5, 2018
- Metronidazole has been shown to cause cancer in mice and rats with long-term use. Talk with the doctor.
- Do not use Flagyl (metronidazole tablets and capsules) for other health problems.
Uses of Flagyl:
- It is used to treat infections.
- It may be given to you for other reasons. Talk with the doctor.
What do I need to tell my doctor BEFORE I take Flagyl?
- If you have an allergy to metronidazole or any other part of Flagyl (metronidazole tablets and capsules).
- If you are allergic to any drugs like this one, any other drugs, foods, or other substances. Tell your doctor about the allergy and what signs you had, like rash; hives; itching; shortness of breath; wheezing; cough; swelling of face, lips, tongue, or throat; or any other signs.
- If you have taken disulfiram within the past 2 weeks.
- If you are less than 12 weeks pregnant. This medicine is not for use in certain patients who are less than 12 weeks pregnant.
- If you are breast-feeding. Do not breast-feed for 24 hours after getting Flagyl (metronidazole tablets and capsules).
This is not a list of all drugs or health problems that interact with Flagyl (metronidazole tablets and capsules).
Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take Flagyl (metronidazole tablets and capsules) with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.
What are some things I need to know or do while I take Flagyl?
- Tell all of your health care providers that you take Flagyl (metronidazole tablets and capsules). This includes your doctors, nurses, pharmacists, and dentists.
- Have blood work checked as you have been told by the doctor. Talk with the doctor.
- This medicine may affect certain lab tests. Tell all of your health care providers and lab workers that you take Flagyl (metronidazole tablets and capsules).
- This medicine may affect how much of some other drugs are in your body. If you are taking other drugs, talk with your doctor. You may need to have your blood work checked more closely while taking Flagyl (metronidazole tablets and capsules) with your other drugs.
- Avoid alcohol and products that have alcohol or propylene glycol in them while taking Flagyl (metronidazole tablets and capsules) and for at least 72 hours after your last dose. Drinking alcohol or taking products that have alcohol or propylene glycol in them, like some cough syrups, may cause cramps, upset stomach, headaches, and flushing.
- Do not use longer than you have been told. A second infection may happen.
- Nervous system problems have happened with Flagyl (metronidazole tablets and capsules). Some people who took Flagyl (metronidazole tablets and capsules) for a long time have had nerve problems that lasted for a long time. Call your doctor right away if you have a burning, numbness, or tingling feeling that is not normal; change in balance or eyesight; dizziness or passing out; headache; not able to sleep; seizures; or trouble speaking. Call your doctor right away if you feel confused, depressed, irritable, tired, or weak.
- If you are 65 or older, use Flagyl (metronidazole tablets and capsules) with care. You could have more side effects.
- Tell your doctor if you are pregnant or plan on getting pregnant. You will need to talk about the benefits and risks of using Flagyl (metronidazole tablets and capsules) while you are pregnant.
How is this medicine (Flagyl) best taken?
Use Flagyl (metronidazole tablets and capsules) as ordered by your doctor. Read all information given to you. Follow all instructions closely.
- To gain the most benefit, do not miss doses.
- Keep taking Flagyl (metronidazole tablets and capsules) as you have been told by your doctor or other health care provider, even if you feel well.
- Take with or without food. Take with food if it causes an upset stomach.
What do I do if I miss a dose?
- Take a missed dose as soon as you think about it.
- If it is close to the time for your next dose, skip the missed dose and go back to your normal time.
- Do not take 2 doses at the same time or extra doses.
See also: Dosage Information (in more detail)
What are some side effects that I need to call my doctor about right away?
WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:
- Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
- Signs of a pancreas problem (pancreatitis) like very bad stomach pain, very bad back pain, or very bad upset stomach or throwing up.
- Not able to control eye movements.
- Chest pain or pressure or a fast heartbeat.
- A heartbeat that does not feel normal.
- Shortness of breath.
- Any unexplained bruising or bleeding.
- Swelling in the arms or legs.
- Redness or white patches in mouth or throat.
- Vaginal itching or discharge.
- This medicine may raise the chance of a very bad brain problem called aseptic meningitis. Call your doctor right away if you have a headache, fever, chills, very upset stomach or throwing up, stiff neck, rash, bright lights bother your eyes, feeling sleepy, or feeling confused.
- Low white blood cell counts have happened with Flagyl (metronidazole tablets and capsules). This may lead to a higher chance of getting an infection. Call your doctor right away if you have signs of infection like fever, chills, or sore throat.
- Some people with Cockayne syndrome have had liver problems when taking Flagyl (metronidazole tablets and capsules). Sometimes, this has been deadly. If you have Cockayne syndrome and are taking Flagyl (metronidazole tablets and capsules), call your doctor right away if you have signs of liver problems like dark urine, feeling tired, not hungry, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.
What are some other side effects of Flagyl?
All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:
- Upset stomach or throwing up.
- Loose stools (diarrhea).
- Hard stools (constipation).
- Not hungry.
- Stomach cramps.
- Stomach pain.
- Metallic taste.
- Feeling sleepy.
- Muscle or joint pain.
- Muscle spasm.
- Lowered interest in sex.
These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.
You may report side effects to the FDA at 1-800-FDA-1088. You may also report side effects at http://www.fda.gov/medwatch.
See also: Side effects (in more detail)
If OVERDOSE is suspected:
If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.
How do I store and/or throw out Flagyl?
- Store at room temperature.
- Protect from light.
- Store in a dry place. Do not store in a bathroom.
- Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
- Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.
Consumer information use
- If your symptoms or health problems do not get better or if they become worse, call your doctor.
- Do not share your drugs with others and do not take anyone else's drugs.
- Keep a list of all your drugs (prescription, natural products, vitamins, OTC) with you. Give this list to your doctor.
- Talk with the doctor before starting any new drug, including prescription or OTC, natural products, or vitamins.
- Some drugs may have another patient information leaflet. Check with your pharmacist. If you have any questions about Flagyl (metronidazole tablets and capsules), please talk with your doctor, nurse, pharmacist, or other health care provider.
- If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
More about Flagyl (metronidazole)
- Flagyl Side Effects
- During Pregnancy or Breastfeeding
- Dosage Information
- Patient Tips
- Drug Images
- Drug Interactions
- Compare Alternatives
- Support Group
- Pricing & Coupons
- En Español
- 207 Reviews
- Generic Availability
- Drug class: amebicides
Other brands: Flagyl ER