Abstract

Elena Villamañán , Yolanda Larrubia , Margarita Ruano , Marta Gallego , Manuel Vélez , Alicia Herrero , Rodolfo Álvarez-Sala

Some adverse drug reactions are due to hypersensitivity reactions. Drug allergy related errors in a handwritten treatment compared with those in an electronic prescribing system, characteristics of reported allergies and economic impact were analyzed. Prospective, observational study was carried out in two phases. 1st Phase (manual prescriptions), errors due to drug allergy were detected when pharmacists registered allergies and then warned the physician. 2nd Phase (electronic prescription) physicians registered allergies and entered treatments in a computerized physician order entry. The program warned avoiding prescription error. 3,682 patients were included. In phase 1, the incidence of prescription errors due to drug allergy was 13.7%, while in phase 2, it was 1.5% (p<0.001). The main drugs involved were antimicrobials. 52 reported allergies (29.7%) were confirmed by a positive allergy test. Alternative therapy was needed in 45 cases (22%), of which 44.1% were due to betalactamic allergy. On average, the alternative antimicrobial treatment multiplied costs per day by 4.4 fold. Computerized physician order entry is an effective tool in preventing medication errors associated with drug allergy. It is important to verify the drug allergy, because incorrectly reported allergies lead to less efficient treatments.