Safety of chemonucleolysis. Adverse effects reported in the United States, 1982-1991

This survey covers 121 "serious" and "unexpected" adverse events after treatment with chymodiactin (chymopapain for injection) among approximately 135,000 patients in the United States. They were reported to the Food and Drug Administration (FDA) within 15 days of notification of the manufacturer between 1982 and the end of 1991. They included fatal anaphylaxis (seven cases), infections (24 cases), hemorrhage (32 cases), and neurologic (32 cases) and miscellaneous (15 cases) events, with a mortality rate of 0.019%. Anaphylactic reactions reported in a postmarketing survey can be attributed to chymopapain itself and infections to lack of asepsis during its administration. The causes of other adverse reactions cannot be as clearly defined, but many are unlikely to have been due to chymopapain or its administration. More careful selection of patients and closer attention to technique during chemonucleolysis have dramatically reduced the incidence of these adverse events, which occur far less frequently than after diskectomy.