A counterirritant is a substance which creates irritation or mild inflammation in one location with the goal of lessening discomfort and/or inflammation in another location. This strategy falls into the more general category of
counterstimulation.
Topical counter-irritants are non-analgesic, non-anesthetic substances or treatments used to treat pain.
Capsaicin
Capsaicin (8-methyl-''N''-vanillyl-6-nonenamide) (, rarely ) is an active component of chili peppers, which are plants belonging to the genus ''Capsicum''. It is a potent Irritation, irritant for Mammal, mammals, including humans, and produces ...
,
menthol
Menthol is an organic compound, specifically a Monoterpene, monoterpenoid, that occurs naturally in the oils of several plants in the Mentha, mint family, such as Mentha arvensis, corn mint and peppermint. It is a white or clear waxy crystallin ...
(mint oil),
methyl salicylate
Methyl salicylate (oil of wintergreen or wintergreen oil) is an organic compound with the formula C8H8O3. It is the methyl ester of salicylic acid. It is a colorless, viscous liquid with a sweet, fruity odor reminiscent of root beer (in which it ...
, and
camphor
Camphor () is a waxy, colorless solid with a strong aroma. It is classified as a terpenoid and a cyclic ketone. It is found in the wood of the camphor laurel (''Cinnamomum camphora''), a large evergreen tree found in East Asia; and in the kapu ...
are examples of counterirritants. Heat and cold therapy and massage relieve pain by counterstimulation.
The US
Food and Drug Administration
The United States Food and Drug Administration (FDA or US FDA) is a List of United States federal agencies, federal agency of the United States Department of Health and Human Services, Department of Health and Human Services. The FDA is respo ...
defines a counterirritant as "An externally applied substance that causes irritation or mild inflammation of the skin for the purpose of relieving pain in muscles, joints and viscera distal to the site of application. They differ from the
anesthetic
An anesthetic (American English) or anaesthetic (British English; see spelling differences) is a drug used to induce anesthesia — in other words, to result in a temporary loss of sensation or awareness. They may be divided into t ...
s,
analgesic
An analgesic drug, also called simply an analgesic, antalgic, pain reliever, or painkiller, is any member of the group of drugs used for pain management. Analgesics are conceptually distinct from anesthetics, which temporarily reduce, and in s ...
s, and
antipruritic
Antipruritics, abirritants, or anti-itch drugs, are medications that inhibit itching (Latin: ''pruritus'').
Itching is often associated with sunburns, allergic reactions, eczema, psoriasis, chickenpox, Fungal infection in animals, fungal infections ...
agents, however, in that the pain relief they produce results from stimulation—rather than depression—of the cutaneous sensory receptors and occurs in structures of the body other than the skin areas to which they are applied as for example, in joints, muscles,
tendon
A tendon or sinew is a tough band of fibrous connective tissue, dense fibrous connective tissue that connects skeletal muscle, muscle to bone. It sends the mechanical forces of muscle contraction to the skeletal system, while withstanding tensi ...
s and certain viscera. The use of these products dates from antiquity."
References
Pain management
Neuropharmacology
{{dermatologic-drug-stub