OBJECTIVES: Determine the number of patients who received antiretroviral therapy (ART) potentially prescribed for prevention of HIV infection in Germany in 2008. METHODS: A representative panel of 1,193,464 patients from different nationwide operating governmental sick funds were analyzed for 2008. Patients with a confirmed diagnosis of HIV (ICD-10: B20-24: 64,8%; R75: 0,9%; U85: 0,6%; U60-61: 14,9%; Z21: 18,8%) were included. In addition, an IMS pharmacy panel (LRx) with 26,815 patients who had received ART identified by ATC Code J05C (Tenofovir was excluded because of use in Hepatitis) in October 2008 to September 2009 were analyzed (54% of all patients with ART-prescriptions). RESULTS: Sick funds: 927 patients with HIV diagnosis were identified (0.08% of the panel), 548 received an ART (treatment rate 59.1%). Pharmacies: 46% of patients received an ART prescription in 4 quarters, 16.9% in 3 quarters, 12.1% in 2 quarters and 24.9% in 1 quarter. 17.5% received prescriptions only on 1 day while of these patients 12% did not have any other ART prescription at least 4 months before or after the analysis period. Patients who received prescriptions on 1 day only, were younger, more often female and received more often Lopinavir/Ritonavir compared to patients who received prescriptions on more days. When extrapolating the numbers to the German governmentally insured population and comparing the numbers from sick funds of patients with a confirmed diagnosis receiving ART with patients who received an ART from pharmacies, about 30% of patients with ART prescription could not be matched to a confirmed diagnosis. CONCLUSIONS: Thirty percent of patients received ART prescriptions without confirmed HIV diagnosis. Twelve percent of patients received ART prescriptions on one day only. Since these patients were younger, more often female and received agents more often used in prophylactic regimens, we assume that prescription of ART for prevention or post-exposure prophylaxis is likely in this group.