Management of possible drug-drug interactions in medical prescriptions received in pharmacies

SUMMARY Introduction Pharmacists and their community pharmacy are responsible for analysing medical prescriptions to identify possible drug-drug interactions. In Cameroon, drug-drug interactions have been examined on several occasions in the hospital settings, but rarely in the community pharmacies, especially from the point of view of management practices. The aim of this study was to describe the management of potential drug-drug interactions in prescriptions received in pharmacies in the Efoulan Health District, Yaoundé, Cameroon. Methodology A cross-sectional descriptive study with prospective data collection was conducted over a period of 07 months from November 2022 to May 2023 in all pharmacies in the Efoulan Health District. All legible prescriptions containing at least two drugs were included. Data were collected using a pre-established and pre-tested form. Interactions were identified using the THERIAQUE® drug database. Data analysis was performed using IBM-SPSS® Version 23.0 software. Results The study involved 67 prescriptions containing 124 drug interactions, averaging 1.8 interactions per prescription. The interactions were mainly pharmacodynamic (74.2%) versus pharmacokinetic (25.8%) in terms of type, and to be taken into account in terms of risk level (52.5%). They were mainly formed by synergism for pharmacodynamic interactions (89.1%) and complexation for pharmacokinetic interactions (59.4%). Prescribers were mainly cardiologists (42.9%) and general practitioners (42.9%). These pharmacological reactions occurred mainly between two non-steroidal anti-inflammatory drugs. The detection rate for interactions was low (21.8%) due to the use of personal knowledge (85.2%) and physical documents (14.8%) for detection. The interactions mainly detected were pharmacokinetic (13.7%) and the combinations to be used with caution (13.7%). The attitudes adopted were, in descending order: advise the patient (55.5%), do nothing (40.8%) and refer the patient back to the prescriber (3.7%). Conclusion Many drug interactions can occur as a result of medical prescriptions. Few of them are detected by dispensers, and the resulting attitudes vary.