Metronidazole for Acne Treatment

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The acne disorder occurs due to an increase in sebum that mixes with dead skin cells, eventually clogging the pores. The result is an inflammatory response that produces pimples, pustules, whiteheads and blackheads. Propionibacterium acnes, a bacteria found normally on the skin, is even more prevalent in acne sufferers, exacerbating the problem. Acne medications, in combination with antibiotics such as metronidazole, can help control sebum and quell the bacterial overgrowth.


Known in the U.S. by its brand name, Flagyl, metronidazole falls under the antibiotic classification of prescription medications. According to the MayoClinic, metronidazole treats bacterial infections throughout the body. Manufactured by Pfizer, and produced in capsule, tablet, suspension solution, gel, cream, lotion and powder form, metronidazole works to kill bacteria and hinder future growth by penetrating the DNA within the bacteria and rendering it unstable.

Time Frame

The cream, lotion or gel forms of metronidazole are the most common forms of the antibiotic prescribed for acne sufferers. However, physicians do also prescribe oral forms of the medication for their patients. The U.S. National Library of Medicine explains that acne patients who use metronidazole should wash their skin with mild soap and water, 15 to 20 minutes prior to application. Only a thin layer of the antibiotic medication is necessary, avoiding the eye area. Marked improvements should appear within three to six weeks.


It is important to consider drug interactions when taking metronidazole for acne. Metronidazole can cause a toxic reaction when taken along with disulfiram, an oral medication used to treat alcoholism. Pfizer reports that metronidazole can increase the potency of some anticoagulant medications, prolonging their effects and interfering with blood clotting. Metronidazole may also cause a decrease in the efficacy of certain types of oral birth controls.


Gastrointestinal disturbances are associated with metronidazole, as well as headaches and a condition known as dry mouth. The University of California at Los Angeles reveals that metronidazole can also cause peripheral neuropathy, when taken in large doses. Some acne patients experience diarrhea, insomnia, nausea and a metallic taste after ingesting metronidazole. Rarer side effects include encephalopathy, pancreatitis and leukopenia.


The safety of metronidazole for women who are pregnant or nursing has yet to be established. What researches do know is that the medication does cross the placental boundary in pregnant women. Pfizer concedes that metronidazole also crosses into the milk or nursing mothers. The effects that metronidazole has on the fetus or newborn child are undocumented.