It contains a resinous and pungent substance known as capsaicin. This chemical relieves pain and itching by acting on sensory nerves. Capsaicin temporarily stimulates release of various neurotransmitters from these nerves, leading to their depletion. Without the neurotransmitters, pain signals can no longer be sent. The effect is temporary. Capsaicin and other constituents in cayenne have been shown to have several other actions, including reducing platelet stickiness and acting as antioxidants.