Pharmacoepidemiology is the study of the utilization and effects ofdrugs in large numbers of people. Drug utilization research is an essential part of pharmacoepidemiology, as it describes the extent, nature and determinants of drug exposure. Over time the distinction between thesetwo terms has become less sharp and they are sometimes usedinterchangeably. This study was conducted in New Kasr Al AiniTeaching Hospital. It is a descriptive retrospective study, applied on 1000 electronic medical records for patients had taken systemic antimicrobialand / or systemic non-steroidal anti-inflammatory drugs. In 2008. It was revealed that 894 (89.4%) of patients had antibioticprescriptions. Cephalosporins showed the highest rate (73.8%) ofprescriptions of total antibiotics prescribed patients, followed bypenicillins (29.7%) then Quinolones and sulpha group (20%) andaminoglycosides (15.8%). Regarding other systemic antimicrobials in thisstudy, they represented about one quarter (25.4%) of the studied sample.It was found that metronidazole alone was significantly higher prescribed(84.6%) than other antimicrobials. Patients who had NSAIDsprescriptions represented (77.4%) of the studied sample. It was found thatparacetamol was the most commonly prescribed NSAIDs (54.3%) ofNSAIDs prescribed patients, this is followed by acetic acid derivativesgroup (35.4%) then salicylates &indoles almost equal percentage of usage(26.5% and 26.1% respectively).