An Antiseptic is a substance that is applied to lesions of the skin. Antiseptics make it less likely a wound gets infected. Commonly used antiseptics include alcohol, iodine and mercury compounds. Antiseptics are different from antibiotics: Antiseptics can only be used on the skin, antibiotics can also be transported through the lymphatic system. They are also different from disinfectants: Disinfectants are used on non-living objects only.