How does this medication work? What will it do for me?

This medication is used to treat infections of the vagina caused by a mixture of certain bacteria and fungi. It contains 2 ingredients. The first ingredient, metronidazole, works by killing certain bacteria. The second ingredient, nystatin, works by killing certain fungi.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

What form(s) does this medication come in?

Vaginal cream
Each full applicator of cream delivers metronidazole 500 mg and nystatin 100,000 units. Nonmedicinal ingredients: glycerin, glyceryl monostearate, methylparaben, propylparaben, purified water, stearic acid, and trolamine.

Vaginal ovules
Each ovule contains metronidazole 500 mg and nystatin 100,000 units. Nonmedicinal ingredient: glycerides of saturated fatty acid (hard fat).

How should I use this medication?

The recommended dose of metronidazole - nystatin vaginal is 1 vaginal ovule, or 1 full applicator of cream, daily, inserted deepinto the vagina, before bedtime, for 10 consecutive days. If using the vaginal ovule, moisten the ovule under water for a second or two just before inserting into the vagina. This will help it to dissolve more easily. If the infection is not cured within 10 days, your doctor may order more medication for you. Make sure to tell your doctor if you still experience symptoms after this time.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you use the medication without consulting your doctor.

It is important to use this medication exactly as prescribed by your doctor. Keep using this medication for the full course of treatment even if you feel better. You should continue to use this medication even if you start to menstruate.

If you miss a dose, use it as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not use a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Store this medication at room temperature, protect it from light and moisture, and keep it out of the reach of children.

Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.

Who should NOT take this medication?

Do not use metronidazole - nystatin vaginal if you:

  • are allergic to metronidazole, nystatin, or any other ingredients of this medication
  • are taking oral (by mouth) metronidazole and also have an active neurological disorder, a history of blood disorders, an underactive thyroid, or underactive adrenal glands

What side effects are possible with this medication?

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

  • constipation
  • darker urine
  • dry mouth
  • granular sensation in the vagina
  • headache
  • heartburn
  • loss of appetite
  • metallic taste or other change in taste sensation
  • minor itching, burning, or irritation in the vagina
  • nausea
  • trouble sleeping
  • vomiting

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

  • difficulty moving
  • fast heartbeat or skipped heartbeats
  • flu-like symptoms (e.g., fever, chills, body aches, sore throat, extreme tiredness)
  • signs of depression (e.g., poor concentration, changes in weight, changes in sleep, decreased interest in activities, thoughts of suicide)
  • signs of liver problems (e.g., nausea, vomiting, diarrhea, loss of appetite, weight loss, yellowing of the skin or whites of the eyes, dark urine, pale stools)
  • tingling feeling on skin

Stop taking the medication and seek immediate medical attention if any of the following occur:

  • chest pain
  • seizures
  • signs of meningitis (e.g., sudden high fever, headache, stiff neck, confusion, nausea and vomiting)
  • signs of a serious allergic reaction (e.g., abdominal cramps, difficulty breathing, nausea and vomiting, or swelling of the face and throat)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Are there any other precautions or warnings for this medication?

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Alcohol: A severe set of side effects including nausea, vomiting, and rapid heartbeat may occur if you consume alcohol while taking metronidazole. Although this usually occurs with the oral (taken by mouth) form of metronidazole, it is possible to experience this reaction with the vaginal form of metronidazole. If you are taking this medication, wait until at least one day after finishing treatment before drinking alcohol.

Confusion/dizziness: This medication may cause confusion or dizziness. Avoid driving or other tasks requiring alertness if the medication affects you in this way.

Effectiveness of other products: Condoms and diaphragms may be less effective while using metronidazole - nystatin vaginal cream or ovule. Other methods of birth control should be used while you are taking this medication.

Liver function: Metronidazole may reduce liver function and can cause liver failure. Although this is more common with the form of metronidazole that is taken by mouth, it can occur with the vaginal form. If you have severe liver disease, this medication may build up in the body, causing side effects.

If you have decreased liver function or have had liver problems in the past as a result of taking metronidazole, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed. Your doctor may want to test your liver function with blood tests while you are taking this medication.

Male partner: When there is evidence of infection in a male sexual partner, he should be treated at the same time with oral metronidazole (taken by mouth) to avoid re-infection.

Neurological side effects: Stop treatment with this medication and see your doctor if muscle incoordination, seizures, or numbness or tingling in the hands or feet occur.

Personal hygiene: Menstrual tampons and soaps with an acid pH should not be used while you are using this medication. These products may promote the growth of fungi, making treatment more difficult.

Side effects: It is possible (but much less likely) that side effects normally associated with the use of oral metronidazole may occur following the use of metronidazole used vaginally.

Underclothing: To help the infection go away more quickly, wear cotton (instead of synthetic) underwear or pantyhose with cotton gussets.

Pregnancy: This medication has not been studied for use by pregnant women. This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately. The applicator should not be used after the seventh month of pregnancy.

Breast-feeding: This medication passes into breast milk. If you are a breast-feeding mother and are using metronidazole - nystatin vaginal, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of using this medication have not been established for children.

What other drugs could interact with this medication?

There may be an interaction between metronidazole - nystatin vaginal and any of the following:

  • alcohol
  • barbiturates (e.g., phenobarbital)
  • BCG vaccine
  • busulfan
  • cyclosporine
  • disulfiram
  • lithium
  • lopinavir
  • phenytoin
  • progesterone (vaginal)
  • sodium picosulfate
  • tipranavir
  • warfarin
  • 5-fluorouracil

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

  • stop taking one of the medications,
  • change one of the medications to another,
  • change how you are taking one or both of the medications, or
  • leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than the ones listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications that you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.