Metronidazole is used to treat a variety of infections. It belongs to a class of antibiotics known as nitroimidazoles. It works by stopping the growth of bacteria and protozoa.
This antibiotic only treats bacterial and protozoal infections. It will not work for viral infections (e.g., common cold, flu). Unnecessary use or overuse of any antibiotic can lead to its decreased effectiveness.
This medication may be taken with food or a full glass of water or milk to prevent stomach upset. Dosage is based on your medical condition, the type of infection being treated, and your response to therapy.
Antibiotics work best when the amount of medicine in your body is kept at a constant level. Therefore, take this drug at evenly spaced intervals.
Continue to take this medication until the full prescribed amount is finished, even if symptoms disappear after a few days. Stopping the medication too early may allow bacteria/protozoa to continue to grow, which may result in a relapse of the infection.
Inform your doctor if your condition persists or worsens.
Dizziness, headache, diarrhea, nausea, stomach pain, loss of appetite, constipation, changes in taste, and dry mouth may occur. If any of these effects persist or worsen, notify your doctor or pharmacist promptly.
This drug may cause urine to darken in color. This is harmless.
Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
Tell your doctor immediately if any of these unlikely but serious side effects occur: unsteadiness, seizures, mental/mood changes (such as confusion), numbness/tingling of hands/feet, painful urination.
Tell your doctor immediately if any of these rare but very serious side effects occur: eye pain, severe/persistent headache, sudden vision changes, stiff/painful neck, sore throat, persistent fever, unusual bleeding/bruising, severe stomach pain, persistent nausea/vomiting.
Use of this medication for prolonged or repeated periods may result in oral thrush or a new vaginal yeast infection (oral or vaginal fungal infection). Contact your doctor if you notice white patches in your mouth, a change in vaginal discharge, or other new symptoms.
A very serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction may include: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.
In the US -
Before taking metronidazole, tell your doctor or pharmacist if you are allergic to it; or to other nitroimidazoles such as tinidazole; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
Avoid alcoholic beverages while taking this medication and for at least 1 day (3 days if you are taking the oral capsules) after finishing this medicine because drinking alcohol may result in severe stomach upset/cramps, nausea, vomiting, headache and flushing.
This drug may make you dizzy. Do not drive, use machinery, or do any activity that requires alertness until you are sure you can perform such activities safely.
The elderly may be at greater risk for side effects while using this drug.
During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.
This medication passes into breast milk. Discuss the risks and benefits with your doctor before breast-feeding. If you are prescribed the single-dose treatment, your doctor may direct you to interrupt breast-feeding for a short time after the dose. Consult your doctor for more details.
Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.
Some products that may interact with this drug include: alcohol-containing products (e.g., cough and cold syrups, aftershave), lopinavir/ritonavir oral solution, "blood thinners" (such as warfarin), busulfan, cimetidine, fluorouracil, lithium, mebendazole, live bacterial vaccines, drugs for seizures (such as phenobarbital, phenytoin).
Avoid disulfiram for 2 weeks before and during treatment with this medication.
Although most antibiotics probably do not affect hormonal birth control such as pills, patch, or ring, some antibiotics may decrease their effectiveness. This could cause pregnancy. Examples include rifamycins such as rifampin or rifabutin. Be sure to ask your doctor or pharmacist if you should use additional reliable birth control methods while using this antibiotic.
This medication may interfere with certain laboratory tests (including liver function tests, blood triglyceride levels), possibly causing false test results. Make sure laboratory personnel and your doctors know you use this drug.
If overdose is suspected, contact a poison control center or emergency room immediately. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include nausea, vomiting, severe dizziness, and seizures.
Do not share this medication with others.
Treatment of certain infections (trichomoniasis) may require that sexual partners be treated as well to avoid re-infection. During therapy, refrain from sexual intercourse or always use a condom.
This medication has been prescribed for your current condition only. Do not use it later for another infection unless told to do so by your doctor. A different medication may be necessary in those cases.
Laboratory and/or medical tests (e.g., blood counts) should be performed from time to time to monitor your progress or check for side effects. Consult your doctor for more details.
If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.
Tablets should be stored at room temperature below 77 degrees F (25 degrees C) away from light. Capsules should be stored at or below room temperature between 59-77 degrees F (15-25 degrees C). Do not store in the bathroom. Keep all medicines away from children and pets.
Information last revised August 2013. Copyright(c) 2013 First Databank, Inc.
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