The answer has to do with ethanol and hydrogen peroxide, which are often ingredients in antiseptics. Both of these agents activate receptors in the body that trigger a burning sensation, said Joseph Glajch, an analytical chemist at Momenta Pharmaceuticals in Cambridge, Massachusetts.

Are antiseptics harmful to skin?

Are antiseptics safe? Some strong antiseptics can cause chemical burns or severe irritation if applied to skin without being diluted with water. Even diluted antiseptics can cause irritation if they're left on skin for long periods of time. This kind of irritation is called irritant contact dermatitis.

Is rubbing alcohol supposed to burn?

Isopropyl alcohol may cause burning, stinging, or a cold feeling where the medicine is applied.