Part I of this article, which appeared in the previous issue of the Journal, considered the potential mechanisms of drug interactions with cyclosporin, and divided the interacting drugs into 2 categories. Drugs that decrease cyclosporin concentrations (e.g. anticonvulsants, rifampicin, etc.) were dealt with first; the authors then moved on to consider the second category, those that increase cyclosporin concentration (macrolide antibiotics, azole antifungal drugs). Part II continues the survey of this category.