A new case of acute renal failure after rifampicin is presented, together with a review of the 36 similar cases published up to date in the literature. Evidence is provided that irregularities in drug intake, either as true intermittent treatment or as discontinuation of continuous therapy, play an important role in the pathogenesis of such reactions. Renal failure appeared after a rather long uneventful interval from the beginning of rifampicin therapy, ranging from 1 month to more than 1 year. Its clinical course was favourable in all but one case; the histological picture was mainly of tubulo-interstitial type. The controversial immunological data reported in the literature are reviewed; an increase of histamine release by rat mast cells has been found in presence of rifampicin plus the serum of our patient: the implications of this finding are discussed, suggesting a possible immunological factor in the pathogenesis of acute renal failure after rifampicin.