Tannic acid is a bitter compound commonly used to protect and heal skin. Natural tannic acid is found in the bark of the oak tree and in the nutgalls of certain insects. Most sexual enhancement products use a vegetable-derived (and vegan-friendly) form of tannic acid.

Tannic acid may promote skin healing, and it has been used for decades to treat burns, rashes, and irritation. It can also have a contracting effect on the skin, and in a concentrated form, it can desensitize sensitive sensitive tissues. For this reason, it is sometimes used as a natural alternative to benzocaine, lidocaine, and other desensitizing ingredients in male enhancement sprays.

While tannic acid is safe in lubes and sex products, it should not be applied to broken skin.