Capsiacin, the ingredient responsible for the burning sensation in cayenne peppers, has shown antibacterial properties in laboratory testing. No clinical trials have proven that cayenne or other peppers containing capsiacin can substitute for antibiotics, however. You can take cayenne and antibiotics at the same time, although no studies have proven any benefit to doing so.

Cayenne’s Actions

In an Egyptian study published in the April 2010 issue of "Foodborne Pathogens and Disease," researchers found that adding cayenne pepper to Kareish cheese completely reduced the amount of yeast in the cheese within two hours and completely reduced the mold count within two days. Cayenne also reduced the total bacterial count. This action is not unique to cayenne, however; many herbs have the same effect. In this study, green peppers produced the same results and parsley and dill also had many of the same effects against bacteria and yeast, although they had a lesser effect on mold.

Significance

Many herbs have antimicrobial actions in the laboratory. This doesn’t mean that they have a strong enough effect to kill bacteria in humans. If your doctor orders an antibiotic, presumably it’s because you have a bacterial infection that needs treatment. Since cayenne has not been proven effective against active infection in people, cayenne alone should not be used as an antibiotic.

Interactions

Capsaicin, the substance responsible for many of cayenne pepper’s beneficial actions and antibiotics don’t appear to react with one another. Drugs.com lists no interactions between the two. A California laboratory study reported in the December 2010 issue of "Xenobiotica" found that capsaicin did not interfere with cytochrome P450 enzymes, which help metabolize many medications, except at very high doses. Taking cayenne with antibiotics should neither increase nor decrease the effectiveness of antibiotics or other medications.

Considerations

If you notice any unusual reactions, call your doctor, since both cayenne and antibiotics can cause reactions, such as rash or gastrointestinal upset. If you take both at the same time, it may be more difficult to determine which one caused the reaction.