Background The pharmacy of Chania General Hospital (CGH) serves outpatients supported by social services. The pharmacy is informed of the patient, doctor and diagnosis.

Purpose This was a descriptive epidemiology study assessing outpatient characteristics, diagnosis according to ICD-10, and ATC classification of the prescribed drug, for the year 2010.

Materials and methods For the year 2010, the CGH pharmacy dispensed 6309 prescriptions for 837 social services outpatients (61.20% of the total outpatient population prescriptions). This cost €46 8250.18. The prescriptions involved 542 pharmacological substances of different ATC identities in a total of 24 149 drug containers. Every medicine prescribed matched an ICD-10 diagnosis. Thus a database of 12967 registered formulations was analysed out of which in 171 cases the diagnosis was not reported and an additional 784 diagnoses were ICD-10 incompatible.

Results Schizophrenia (F20) was the frequent diagnosis at 14.1%, followed by ischaemic cardiomyopathy – coronary artery disease (I25.1) at 12.9% and affective psychosis (F25.2) as the third most frequent diagnosis (11.10%). 93.93% of the prescribed substances for the dominant diagnosis were central nervous system (CNS) drugs with olanzapine (N05AH03) being the most popular (7.8%). The most common drug prescribed for coronary artery disease outpatients was acetylsalicylic acid (N02BA01) (13.5%) and affective psychosis patients received mostly venlafaxine (N06AA22) (8.9%).

Conclusions Mental illness is highly prevalent in the population of poor indigent and immigrant patients which implies difficulties with social reintegration. Evidence-based positive correlation between acetyl salicylicacid and protection against acute myocardial infarction and sudden death justifies its extended use. These data should be kept in mind when policies for this particular population are reviewed.