Addiction and abuse of antipyretic analgesics has been recognized early after the turn of this century. The incidence markedly increased and the syndrome spread over many countries in the first half of the 20th century. The syndrome and its pathology, consisting of renal papillary necrosis and tubulo-interstitial nephritis, was first described in the medical literature in the early 1950's in Switzerland by Spühler and Zollinger, who rightly suspected chronic analgesic (Saridon) intoxication as being the cause in their cases. Clinically the disease is characterized by slowly progressive renal failure with renal colics from passage of necrotic papillae. Death from uremia is common unless dialyzed. The disease has been particularly prevalent in certain areas of Australia, Belgium, Western Germany, in Switzerland and some other countries. The nephrotoxic agents are mixtures of salicylates (aspirin) with phenacetin or acetaminophen. The principal nephrotoxic compound is probably aspirin--the aminophenol derivatives increasing its nephrotoxicity. However, all these components alone may cause--exceptionally--the syndrome. Rarely some newer, nonsteroid analgesics (NSAID's) can also be nephrotoxic. Phenacetin has--in particular in compound mixtures--mood-altering (euphoric) properties, giving rise to craving, addiction and chronic abuse. Addiction has been greatly facilitated by the over-the-counter availability of these cheap analgesic mixtures. Mass addiction--and abuse--may occur in all kinds of communities, in factories or families because of the euphoric effect, taking away fatigue and weariness and increasing productivity. There is a relation between the per capita consumption of antipyretic analgesics and analgesic nephropathy in several countries and in certain districts. The pattern of sales and mass consumption (and the incidence of nephropathy) is substantially promoted by the local presence of production facilities, usually accompanied by vigorous sales and advertising policies. Individual addiction usually occurs in psychoneurotic females often with social and marital problems and mental instability, often with long histories of headaches, backpains, and other, often psychogenic disorders. Analgesic nephropathy is often complicated by anemia, peptic ulcer, premature aging and atherosclerosis and in 8-10% by uro-epithelial carcinoma (the so called analgesic syndrome). The diagnosis depends largely on the history of chronic abuse of analgesics, which is often doggedly denied, hampering the diagnosis.(ABSTRACT TRUNCATED AT 400 WORDS)