Capsaicin is an alkaloid of peppers. The biological substance is known as a food seasoning, but is also used in phytomedicine. Irritation of heat receptors is the main effect of capsaicin.
What is capsaicin?
Capsaicin is an alkaloid of peppers. Irritation of heat receptors is the main effect of capsaicin, such as heat patches. Capsaicin is a natural substance found in the capsicum bell pepper (Capsicum). Especially the varieties known as chili have capsaicin in high concentrations. Capsaicin is one of the alkaloids, which are alkaline (lye-like) biogenic nitrogen compounds. Like most alkaloids, capsaicin is excellently fat-soluble. Alkaloids are found in almost all nightshade plants but also in other plants. They are partly known to be toxic, but in medical doses they are also known to be medicinal (examples: the solanine of the potato, caffeine or morphine). Capsaicin in the fruits of the bell pepper is part of the secondary metabolism of the plant. This means that although capsaicin is not vital for the plant, it is an advantage in the “struggle for existence”. The spicy and also healing effect of peppers is essentially based on capsaicin.
Pharmacological action
Capsaicin irritates pain receptors in the skin and mucous membranes. These “nociceptors” are endings of sensory nerve cells that also register heat and the sensation of burning and transmit them to the brain. There, the perception of the well-known hotness arises, which is therefore basically a heat perception. The perception is therefore not based on a temperature stimulus, but on a biochemical effect. Therefore, one can speak of a kind of hallucination. (Analogous to this is the effect of menthol in the area of cold perception). As our body perceives heat or warmth under the influence of capsaicin, a series of defensive reactions occur. First, the capillaries in the skin and mucous membrane dilate (vasodilation), resulting in increased blood flow. This in turn now leads to a physical, i.e. “actual”, development of heat. Via the path of nervous and hormonal control, contact with capsaicin leads to increased saliva secretion and increased gastric juice secretion. In addition, the organism tries to defend itself against the supposed heat development with lacrimation and perspiration. In addition to these direct effects on the organism, capsaicin also has antibiotic properties. The killing of bacterial pathogens and fungi is determinant for the disinfecting effect of capsaicin.
Medical application and use
Capsaicin is included in some medications due to its warming and circulation-enhancing properties. Heat patches with capsaicin relieve the discomfort of sciatica or pain caused by rheumatism. Although capsaicin does not eliminate the causes of the conditions in question, it does provide the patient with some relief. In the case of muscular pain, however, the self-healing power of the tissue is strengthened by an improved saustoff supply. It could have a similar effect in the treatment of fibromyalgia. Against this “mutlilocular pain syndrome” the use of capsaicin is discussed. In addition, capsaicin is considered to be an antipruritic agent. However, the mechanism of action is unclear, as is the causal effect that capsaicin has on psoriasis. In small doses, capsaicin is used in ointments against nerve pain, whereby the effect is not immediate but delayed for a few days. Capsaicin is used as a food seasoning to stimulate appetite and as a digestive aid. The use of capsaicin as a banned doping agent in equestrian sports should also not go unmentioned. The pepper sprays known for self-defense and defense against pests also contain capsaicin.
Risks and side effects
Capsaicin should always be used cautiously and in the prescribed dosages due to its strong irritant properties. Otherwise, unpleasant skin symptoms such as itching may result. Capsaicin can even cause a rash with blistering. It is therefore advisable to always wear disposable gloves when applying creams containing capsaicin. Capsaicin should only ever be applied to the target area when used externally; the sensitive mucous membranes in particular must be protected! Infants and small children must not be treated with the alkaloid under any circumstances.Oral ingestion of capsaicin (edible spice) can cause respiratory distress and nausea. Therefore, emergency doctors are always present at the competitions of chili fanatics, which are justifiably criticized. This urges the necessary caution in dealing with capsaicin.
