Toxicity of “Eucupin” in Local Analgesia.

Abstract

A group study for the evaluation of local analgesics by clinical trial was organized at the University of California Hospital in December, 1927. Prolongation of analgesia was especially desired. The analgesics first studied were 0.5% and 1.0% procaine and “tutocaine” to which 0.1% “eucupin” had been added, as suggested by De Takats. 1 These solutions gave extremely satisfactory analgesia, lasting in some cases as long as 24 to 36 hours. Local reactions, such as erythema, induration, and delayed healing occurred, however, in the majority of cases. Extensive sloughs of the skin and subcutaneous structures that greatly prolonged the post-operative course, developed in 2 out of 15 patients. Four others suffered minor sloughing.

These reactions suggested excessive toxicity for the infiltrated structures and made the abandonment of the “eucupin” containing solutions advisable. As a further check, a series of controlled intradermal wheals were made, using 10 medical students as subjects. The solutions used were 1% procaine and 1% “tutocaine” to which 0.1% “eucupin” had been added, and solutions of 1% procaine and 1% “tutocaine” for controls. The results checked the clinical observations. The average duration of analgesia for the 1% procaine and the 1% “tutocaine” was 2 hours. The average duration of analgesia for the 1% procaine-0.1% “eucupin” mixture was 20 hours; for the 1% “tutocaine”-0.1% “eucupin,” 24 hours. There was no evidence of local tissue damage at the site of either the procaine or “tutocaine” injections. Local reactions occurred in 6 cases (60%) with each of the “eucupin” solutions. These varied in intensity from a persistent erythema to definite sloughing. There were 2 small sloughs from the procaine-“eucupin” and 3 sloughs from the “tutocaine”-“eucupin”. Of the latter, 2 were quite small, but the third was nearly 2 cm. in diameter and accompanied by marked vesication and erythema.