Flagyl is a prescription drug used for treating certain types of bacterial and parasitic infections, including some sexually transmitted infections. The antibiotic works to kill bacteria and parasites by entering the bacterial or parasite cell and causing a reaction that produces free radicals (molecules that can damage and destroy cells). Flagyl is available in the form of short-acting tablets, long-acting tablets, capsules, and an injection.
What Is Flagyl?
Flagyl® (metronidazole) is a prescription antibiotic approved to treat a variety of different infections, including certain sexually transmitted infections. It is especially useful for treating infections caused by parasites and anaerobic bacteria (certain bacteria that do not require oxygen to survive).
(Click Flagyl Uses for more information on what the medication is used for, including possible off-label uses.)
Who Makes It?
Brand-name Flagyl is made by Pfizer, Inc. Generic versions of the medication are made by various different manufacturers.
How Does It Work?
In order to work, Flagyl must enter the bacterial 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 Flagyl works to kill bacteria or parasites.
When and How to Take Flagyl
Some general considerations include the following:
- Flagyl comes as tablets, long-acting tablets (Flagyl ER), and capsules (Flagyl 375). It is also available in an injectable form. It is taken one to four times daily, depending on the particular use.
- You can take the regular tablets or capsules with food or on an empty stomach. However, long-acting tablets must be taken on an empty stomach, at least one hour before or two hours after a meal.
- Be sure to take your doses of this medication at the same time(s) each day. Taking doses too far apart may make the drug less effective, and taking them too close together may increase the risk of side effects.
- For the medication to work properly, it must be taken as prescribed. Flagyl will not work if you stop taking it too soon.