Emtricitabine FTC is a cytosine analogue, recently introduced in clinical practice for the treatment of HIV patients. In order to evaluate the safety and efficacy of antiretroviral regimen containing emtricitabine in the clinical practice, we performed an observational study on all patients starting a regimens containing emtricitabine in a clinical unit. Data were collected from clinical charts and inserted into a computerized database. We evaluated the following outcome measures: probability of interruption of FTC-regimen due to side effects; time to virologic suppression in patients with detectable viral load at baseline; time to loss of virologic efficacy in patients with virologic suppression at baseline, immunologic variations. In the period January 2005- March 2006, overall 150 patients started a FTC-regimen; 16.7% of them were naïve to antiretroviral treatment. The median period of observation was 80 days (IQR 26-190) and 26.7% of patients had a longitudinal observation longer than 24 weeks. At last observation, 82% of patients were still continuing baseline regimen and 13.3% interrupted FTC. Efficacy analysis in viremic patients showed that 6 months-probability of virologic success during treatment with FTC was 74.7%. Our preliminary observation show that FTC-regimens seems effective and tolerable in real practice.