 Although capsaicin creams have been used to treat psoriasis for reduction of itching, a review of six clinical trials involving topical capsaicin for treatment of pruritus concluded there was insufficient evidence of effect.There is insufficient clinical evidence to determine the role of ingested capsaicin on several human disorders, including obesity, diabetes, cancer and cardiovascular diseases.Capsaicinoids are also an active ingredient in riot control and personal defense pepper spray agents.