While many health districts recognise that irrational prescribing leads to wastage of drugs, few monitor prescribing practices. We investigated drug use in government health facilities in the Wassa West district of Ghana. Retrospective prescribing data were obtained from 700 outpatients' clinical record cards in 7 government health facilities in the district. Prescribing patterns were significantly worse in the health centres than in the district hospital in terms of polypharmacy, use of injectable drugs and antibiotics. Overall, 4.8 drugs were prescribed per patient, 97% of drugs were on the national essential drugs list and 65% of drugs were prescribed by their generic names. Antibiotics and injectable drugs were prescribed for 60% and 80% patients respectively. The observed patterns were related to the cadre of prescribers, availability of diagnostic facilities, participation in recent refresher training and patient demand. Measures to improve prescribing practices are discussed.