Current antiretroviral treatment (ART) guidelines recommend different combinations that have led to major improvements in the management of HIV and AIDS in the developed and developing world. With the rapid approval of many agents, health care providers may not be able to familiarise themselves with them all. This lack of knowledge leads to increased risk of dose- prescribing errors, especially by non-HIV and AIDS specialists. The purpose of this retrospective non-experimental, quantitative drug utilisation study was to evaluate if antiretrovirals (ARVs) are prescribed according to the recommended prescribed daily doses (PDDs) in a section of the private health care sector in South Africa (SA). Analysed ARV prescriptions (49995, 81096 and 88988) for HIV and AIDS patients were claimed from a national medicine claims database for the period 1 January 2005 through to 31 December 2007. ARV prescriptions prescribed by general practitioners (GPs) with PDDs not according to the recommended ARV dosing increased dramatically, from 12.33% in 2005 to 24.26% in 2007. Those prescribed by specialists (SPs) increased from 15.46% in 2005 to 35.20% in 2006 and decreased to 33.16% in 2007. The highest percentage of ARV prescriptions with PDDs not according to recommended ARV dosing guidelines was identified in ARV regimens with lopinavir−ritonavir at a PDD of 1066.4/264 mg and efavirenz at a PDD of 600 mg prescribed to patients in the age group of Group 3 (19 years > age ≤ 45 years). These regimens were mostly prescribed by GPs rather than SPs. There is a need for more education for all health care professionals and/or providers in the private health care sector in SA on recommended ARV doses, to avoid treatment failures, development of resistance, drug-related adverse effects and drug interactions.OpsommingHuidige riglyne vir behandeling met antiretrovirale middels beveel verskillende kombinasies aan wat tot groot verbetering in die beheer van MIV en VIGS in die ontwikkelde en ontwikkelende wêreld gelei het. Met die vinnige goedkeuring van talle nuwe middels kan dit gebeur dat verskaffers van gesondheidsorg nie kan bybly om hulle hiermee op hoogte te hou nie. Hierdie gebrek aan kennis lei tot ‘n hoër risiko vir foute in die voorgeskrewe dosis en veral deur persone wat nie spesialiste in MIV en VIGS is nie. Die doel van hierdie nie-eksperimentele, retrospektiewe, kwantitatiewe studie van die gebruik van geneesmiddels was om te bepaal of antiretrovirale middels in ‘n deel van die privaat gesondheidsorgsektor in Suid-Afrika (SA) volgens die aanbevole voorgeskrewe daaglikse dosisse (VDD) voorgeskryf word. Voorskrifte van antiretrovirale middels (49995, 81096 en 88988) aan pasiënte met MIV en VIGS wat in die periode van 1 Januarie 2005 tot 31 Desember 2007 van ‘n nasionale medisyne databasis geëis is, is ontleed. Voorskrifte van antiretrovirale middels deur algemene praktisyns (APs) met VDDs wat nie volgens die aanbevole dosisse vir antiretrovirale middels was nie, het dramaties van 12.33% in 2005 tot 24.26% in 2007 toegeneem. Die wat deur spesialiste (SPs) voorgeskryf is, het van 15.46% in 2005 tot 35.20% in 2006 toegeneem en in 2007 tot 33.16% gedaal. Die hoogste persentasie van voorskrifte vir antiretrovirale middels met VDDs wat nie volgens die riglyne was nie, was in die regimens met lopinavir−ritonavir met ‘n VDD van 1066.4/264 mg en efavirens met ‘n VDD van 600 mg wat aan pasiënte in die ouderdomsgroep van ouer as 19 tot en met 45 jaar voorgeskryf is. Hierdie regimens is meer deur APs as deur SPs voorgeskryf. Daar is ‘n behoefte aan nog opleiding van alle gesondheidsprofessies en/of voersieners in die privaat gesondheidsorgsektor in SA oor die aanbevole antiretrovirale middel-dosisse om mislukking van behandeling, ontwikkeling van weerstand, nadelige effekte vanweë geneesmiddels en geneesmiddel interaksies te voorkom.