Two high-performance liquid chromatographic methods using UV detection are presented for the determination of two different groups (A and B) of drugs used in the suppression of human immunodeficiency virus (HIV). Group A is comprised of six nucleosidic reverse transcriptase inhibitors, viz. zalcitabine, lamivudine, stavudine, didanosine, zidovudine and ziagen. Group B consists of seven drugs four of which are protease inhibitors (PIs) and three of which are non-nucleosidic reverse transcriptase inhibitors (NNRTIs). The PIs are: indinavir, nelfinavir, saquinavir and ritonavir. The NNRTIs are: nevirapine, delavirdine and efavirenz. Groups A and B require separate aliquots of serum for extraction and must be chromatographed separately.