Japanese camphor (Cinnamomum camphora) has a long history of topical use for itching (pruritus), and its mechanism of action has been partially elucidated in modern research. Camphor acts as a counterirritant. When applied to the skin, it stimulates nerve endings that transmit a cooling sensation and, through this mechanism, helps mask the sensation of itching. This property is recognized in pharmacological references and is the basis for camphor's inclusion in several over-the-counter anti-itch formulations, often in combination with menthol or other soothing agents.

Regulatory agencies such as the U.S. FDA allow the external use of camphor (in concentrations below 11%) for the temporary relief of itching and minor skin irritations, indicating a level of scientific and clinical acceptance. Peer-reviewed studies and dermatology references (e.g., in Fitzpatrick's Dermatology and Dermatologic Therapy) note the efficacy of camphor as a topical antipruritic, although head-to-head clinical trials are limited.

However, camphor should be used with caution due to potential toxicity if ingested or applied inappropriately, especially in children. Overall, the use of Japanese camphor for itching is supported by both traditional practice and moderate scientific evidence, earning a mid-level rating for evidence.