Menthol is an organic compound made from the oils of corn mint, peppermint, or other mints.  It is used as a flavoring and in decongestants and pain relief.

Menthol produces a cooling effect by blocking the calcium current along the nerves responsible for detecting temperature. The message that the brain receives from the nerve endings is that the skin or body is cooling.

Menthol is used in SOTA's ice pain gel as a counterirritant. It works by causing the skin to feel cool and then warm. These feelings on the skin distract you from feeling the aches and pains deeper in your muscles and joints.