Quantitative aspects of longterm analgesic intake are presented, based on a case-control-study on the relation between regular analgesic intake and endstage renal failure in the area of West Berlin (1984-86). Lifetime analgesic consumption of more than 1000 persons were investigated. A total of 285 longterm analgesic users (185 cases = 35.8%; 100 controls = 19.3%) were detected. An odd ratio of 2.44 (95% CI: 1.77-3.39) was computed. Regular analgesic intake was defined as an intake of at least 15 analgesic doses per month continuously over a period of at least 12 months. 90% of the regular users preferred mixed analgesics compounds, in most cases with the psychotropic additive caffeine.