As a supplement to a previous paper [Dreschler et al.: Audiology 1985; 24:387-395] high-frequency (HF) audiometry was applied to compare the ototoxic effects of two different drug administration protocols for cis-platinum (CDDP). In both subgroups, HF audiometry considerably enhanced the early detection of ototoxicity. Marked differences between treatments have been established both in the pattern of onset of the damage and in the relation between dose and damage severity. For subjects treated with platinum derivatives, the thresholds at 12 and 14 kHz prove to be especially important. The results suggest that for these subjects the measurement of only a single frequency may be considered: with a minimum of effort, most of the increased sensitivity for a complete HF audiogram can be obtained. Finally, the relation between threshold deteriorations above 8 kHz and threshold deteriorations in the conventional range of audiometric frequencies has been investigated.