OBJECTIVES: Antipsychotic medicines are commonly prescribed to elderly patients.  These patients are at an increased risk of adverse drug events because of age-related pharmacodynamic and pharmacokinetic changes.  The primary aim of the study was to determine antipsychotic prescribing patterns and cost to patients aged 60 years and older in a private health care sector primary care patient population in 2008 and 2009. METHODS: A retrospective, exposure-cohort drug utilisation study was conducted on prescription data of a pharmacy group in South Africa for 2008 and 2009.  No diagnoses were available.  All records for antipsychotics (MIMS category 1.5) for patients 60 years and older were extracted for analysis. RESULTS: A total of 1 800 patients in 2008 and 3 086 patients in 2009 received 7 877 and 14 538 antipsychotic products at a sales value of R2 785 896 and R4 928 127, respectively.  The average cost per antipsychotic product was R353.67 in 2008 and R338.98 in 2009.  Most patients were female (61.78% in 2008 and 57.87% in 2009).  Tablets were the preferred dosage form.  Risperidone (37.55% in 2008, and 38.20% in 2009), quetiapine (27.56% and 28.88%) and olanzapine (10.91% and 10.24%) together accounted for more than 75% of antipsychotics prescribed to the elderly.  A high percentage of atypical antipsychotics (84.23% in 2008 and 85.14% in 2009) were prescribed.  Differences were observed between 2008 and 2009 with respect to the prescribing frequency of the atypical antipsychotics (chi2 = 32.624;  d.f. = 6;  p <0.0001). CONCLUSIONS: Prescribing patterns were relatively similar in both years.  The dosages and duration of treatment of antipsychotics should be investigated in relation to the diagnoses for which they are prescribed.  It is recommended that diagnoses be included in databases and also that qualitative studies be conducted to determine possible side effects experienced by patients.