 One 2017 review of clinical studies having limited quality found that high-dose topical capsaicin (8%) compared with control (0.4% capsaicin) provided moderate to substantial pain relief from post-herpetic neuralgia, HIV-neuropathy, and diabetic neuropathy.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.