THE EFFECTS of penicillin administered parenterally on the clotting mechanism of blood is a controversial subject. In order to determine the efficacy of penicillin as a thromboplastic agent, this study was instituted.
Many references concerning this subject are available in the literature. Fleming and Fish,1 in 1947, did a series of experiments in vitro testing the coagulating property of penicillin. Their conclusion had little bearing on the clinical and systemic use of penicillin. They demonstrated that in vitro and locally penicillin had no effect on the clotting mechanism of blood. Moldavsky2 and his associates, in 1945, tested the same properties of penicillin on patients, administering the drug orally and intramuscularly. Their conclusions apparently had considerable practical clinical significance. They found that (a) the clotting time of blood diminished as the level of penicillin rose in blood; (b) there was a decrease in the bleeding time with penicillin administration,