Prompted by previously results of systemic steroid treatment of symptoms of prolapsed lumbar disc, which appeared to be promising, dexamethasone phosphate was tested in a controlled, double-blind clinical study. 52 patients were included in the study: 25 received dexamethasone phosphate, 24 received placebo and 3 patients dropped out. Upon termination of the study the two groups were found to be comparable as to age, sex, duration of symptoms and degree of heavy work. We were not able to demonstrate any effect of dexamethasone phosphate on the following parameters pain, paraesthesia, paresismuscular weakness, disturbances of reflexes, and Laseque. Nor was there any difference in the length of hospitalization.