Metronidazole (
Flagyl®, MetroCream
®, MetroGel
®, MetroGel-Vaginal
®, MetroLotion
®, Noritate
®, Vandazole
®) is a prescription antibiotic approved to treat a variety of different infections. It comes in several different forms, such as tablets, skin creams and lotions, or vaginal cream. The medication is especially useful for infections caused by parasites and anaerobic bacteria (bacteria that do not require oxygen to survive).
In order to work, metronidazole must enter the bacteria or parasite cell. The cells then cause a chemical reaction to occur with the medication. This reaction produces free radicals, molecules that can damage and destroy cells. This is presumably how metronidazole works to kill bacteria or parasites.
When and How to Take This Medication
General considerations for those taking metronidazole include the following:
- This medication comes in several different forms. The particular directions for each product can vary substantially, so be sure to refer to the information for your specific product.
- You can take regular, short-acting metronidazole tablets or capsules with food or on an empty stomach. However, long-acting, extended-release metronidazole tablets must be taken on an empty stomach, at least one hour before or two hours after a meal.
- For the medication to work properly, it must be taken as prescribed. Do not miss doses or stop taking this antibiotic earlier than your healthcare provider recommends, as bacterial resistance may develop.
The dose of metronidazole your healthcare provider recommends will vary, depending on a number of factors, including:
- The particular metronidazole product
- The type and severity of your infection
- How you respond to the antibiotic
- Other medications you are taking
- Your weight (for children)
- Other medical conditions you may have.
As is always the case, do not adjust your dose unless your healthcare provider specifically instructs you to do so.
Side Effects of Metronidazole
Just like any medicine, metronidazole can cause side effects. However, not everyone who takes the drug will experience problems. Most people actually tolerate it quite well. If side effects do occur, in most cases, they are minor and either require no treatment or can easily be treated by you or your healthcare provider. Serious side effects are less common.
The specific side effects a person can experience depend on the particular form of metronidazole. Common ones include but are not limited to:
- Headaches
- Nausea
- Metallic taste in the mouth.
(Click Metronidazole Side Effects to learn more, including potentially serious side effects you should report immediately to your healthcare provider.)
What Should I Tell My Healthcare Provider?
You should talk with your healthcare provider prior to taking metronidazole if you have:
Also, let your healthcare provider know if you are:
Make sure to tell your healthcare provider about any other medications you are taking, including prescription and nonprescription medicines, vitamins, and herbal supplements.
What If I Overdose on This Medicine?
An overdose of metronidazole may cause the following symptoms:
- Nausea
- Vomiting
- Coordination problems
- Seizures
- Unusual or unpleasant sensations in the hands or feet.
If you happen to take too much of this drug, seek medical attention right away.
How Should Metronidazole Be Stored?
Metronidazole products should be stored at room temperature, away from moisture and heat. Keep this and all other medications out of the reach of children. Refer to the storage directions for your particular product.
What Should I Do If I Miss a Dose?
As with all antibiotics, it is important to avoid missing doses. If you do miss a dose, simply take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and continue with your regular schedule. Do not take a double dose.
Many different prescription metronidazole products are available in several different forms
(see Metronidazole Prescription Drugs for more information). Many (but not all) are available in generic form.
