Metronidazole

Drug Information

Metronidazole is an antibiotic used to treat a variety of bacterial and parasitic infections, such as amebiasis, trichomoniasis, and giardiasis. It is also used as a component of multidrug antibiotic combinations to heal stomach and duodenal ulcers caused by Helicobacter pylori infections. Metronidazole is available alone and in a combination product.

From Vaginal Intro (733)

Metronidazole (vaginal) is an intravaginal antibiotic used to treat vaginal infections caused primarily by bacteria. is also available as oral and topical medications.

Common brand names:

Flagyl, MetroGel Vaginal, Noritate, MetroCream, MetroGel, Vandazole

Summary of Interactions with Vitamins, Herbs, & Foods

Types of interactions:BeneficialAdverseCheck

Replenish Depleted Nutrients

  • Vitamin B12

    Neomycin can decrease absorption or increase elimination of many nutrients, including calcium, carbohydrates, beta-carotene, fats, folic acid, iron, magnesium, potassium, sodium, and vitamin A, vitamin B12, vitamin D, and vitamin K. Surgery preparation with oral neomycin is unlikely to lead to deficiencies. It makes sense for people taking neomycin for more than a few days to also take a multivitamin-mineral supplement.

  • Vitamin K

    Several cases of excessive bleeding have been reported in people who take antibiotics. This side effect may be the result of reduced vitamin K activity and/or reduced vitamin K production by bacteria in the colon. One study showed that people who had taken broad-spectrum antibiotics had lower liver concentrations of vitamin K2 (menaquinone), though vitamin K1 (phylloquinone) levels remained normal. Several antibiotics appear to exert a strong effect on vitamin K activity, while others may not have any effect. Therefore, one should refer to a specific antibiotic for information on whether it interacts with vitamin K. Doctors of natural medicine sometimes recommend vitamin K supplementation to people taking antibiotics. Additional research is needed to determine whether the amount of vitamin K1 found in some multivitamins is sufficient to prevent antibiotic-induced bleeding. Moreover, most multivitamins do not contain vitamin K.

Reduce Side Effects

  • Probiotics

    The yeast Saccharomyces boulardii may help restore microbial balance in the intestines and prevent pseudomembranous colitis (PMC), an intestinal disorder caused by infection with Clostridium difficile. Even when Clostridium difficile is successfully treated with antibiotics, symptoms recur in about 20% of cases. Saccharomyces boulardii has been shown in controlled trials to reduce recurrences when given as an adjunct to antibiotic therapy.

Support Medicine

  • Probiotics
    In one study, taking 500 mg of Saccharomyces boulardii twice daily enhanced the effectiveness of the antibiotic vancomycin in preventing recurrent clostridium infection. Therefore, people taking antibiotics who later develop diarrhea might benefit from supplementing with saccharomyces organisms.

Reduces Effectiveness

  • Khat (Catha edulis) is an herb found in East Africa and Yemen that has recently been imported into the United States. Studies have shown that chewing khat significantly reduces the absorption of ampicillin, which might reduce the effectiveness of the antibiotic. Therefore, people taking ampicillin should avoid herbal products that contain khat.

Potential Negative Interaction

  • none

Explanation Required

  • Milk Thistle

    Milk thistle has been reported to protect the liver from harm caused by some prescription drugs. While milk thistle has not yet been studied directly for protecting people against the known potentially liver-damaging actions of metronidazole, it is often used for this purpose.

The Drug-Nutrient Interactions table may not include every possible interaction. Taking medicines with meals, on an empty stomach, or with alcohol may influence their effects. For details, refer to the manufacturers’ package information as these are not covered in this table. If you take medications, always discuss the potential risks and benefits of adding a new supplement with your doctor or pharmacist.

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