Clinical and experimental evaluation of thephorin ointment

1. 1. Thephorin Ointment was evaluated clinically in 161 patients with a variety of pruritic dermatoses. Of these, 120, or 74.5 per cent, were helped. Thirty-four of those benefited obtained equal relief from the Carbowax base. In 86 patients, however, the subsidence of pruritus was unquestionably due to Thephorin since their itch was not relieved with the Carbowax alone. The antipruritic effect was best in cases of atopic dermatitis, and of pruritus ani, vulvae, and scroti. The comparatively high incidence of success and the low sensitizing index (0.6 per cent) warrants the keeping of Thephorin Ointment in the dermatotherapeutic armamentarium. However, the salve should be used with the realization of the occurrence of 2.5 per cent of contact-type reactions. 2. 2. Experimental evidence is presented that Thephorin Ointment has no significant effect on histamine-induced wheal formation, but that it markedly inhibits the histamine flare. This suggests that Thephorin acts upon the axon reflex. This action may be due to an anesthetic effect on the sensory nerve endings in the skin or to an antagonism to acetylcholine released on the arterioles at the nerve endings. Evidence is presented that favors the theory that the inhibition of the histamine flare must be attributed to the anesthetic action of Thephorin Ointment on the sensory nerve endings of the skin. It is inferred that its antipruritic effect is based on the same mechanism. 3. 3. Thephorin Ointment inhibits erythema solare if it is applied prior to the exposure to ultraviolet light. No inhibition occurs if the salve is applied after exposure.