Forty-three per cent of prescriptions generate drug therapy alerts in community pharmacies, with one in six patients accounting for 80 per cent of the alerts, according to Pharmacoepidemiology and Drug Safety.

Researchers retrospectively analysed alerts generated by a clinical decision support system used by 123 community pharmacies in Holland. The analysis included almost 1.7 million prescriptions from 81,742 patients.

Forty-three per cent of prescriptions generated at least one drug safety alert, most frequently drug-drug interactions (15 per cent of prescriptions), drug-disease interactions (14 per cent), duplicate medications (13 per cent) and dosing (7 per cent). Prescriptions issued to 16 per cent of patients accounted for 80 per cent of the alerts.

Prescribing a risky business...

Interactions between ACE inhibitors/angiotensin II antagonists plus diuretics were the most frequent drug-drug interaction alert (14.8 per cent of alerts), followed by antidiabetics plus beta-blockers (9.1 per cent) and non-steroidal anti-inflammatory drugs plus ACE inhibitors/angiotensin II antagonists (4.8 per cent).

The most frequent drug-disease interaction alerts were ACE inhibitors in diabetes (9.2 per cent of alerts), beta-blockers in obstructive pulmonary disease (8.5 per cent) and diuretics in renal impairment (7.9 per cent).

^{(DOI:10.1002/pds.3915)}