Capsaicin, (trans-8-N-nanillyl-6-noneamide), is a major lipophilic alkaloid of Capsicum fruits which produces burning sensation in the mouth of the consumer. Capsaicin is mainly located in the vesicles or vacuoles like sub cellular organelles of the epidermal cells of the placenta in the pods. The highest concentration of capsaicin is found in the ovary and in the lower flesh (tip) and lowest concentration of capsaicin is in seeds.

Capsaicin is a safe and effective analgesic agent in the management of arthritis pain, herpes, diabetic neuropathy, post mastectomy pain and headache. It is found that capsaicin can provoke programmed cell death in human prostate cancer. Capsaicin can be externally used as a remedy for painful joints and to stop bleeding. Capsaicin also serves as a local anesthetic agent to ulcerated tissue in the stomach. Capsaicin creams are used to treat psoriasis.

Figure 1: structure of capsaicin

Capsaicin can cause skin irritation. It can severely irritate the eyes and it is found to cause corneal lesions. Capsaicin temporarily causes bronchoconstriction, coughing nausea and incoordination in the upper body of humans following inhalation. People suffering from asthma and other respiratory diseases are more sensitive to capsaicin than other individuals. Capsaicin produces its repellant effects when it contacts either eye or respiratory tracts mucous membrane such as inability to vocalize, diarrhea, vomiting and temporary blindness.