Potentially inappropriate medications, drug-drug interactions, and prescribing practices in elderly patients: a cross-sectional study.

Objective: To evaluate potentially inappropriate medications, potential drug-drug interactions, and prescribing practices in elderly ambulatory patients.

Methods: We carried out a cross-sectional study on 275 elderly patients attending different outpatient departments. We used the Screening Tool for Older Person's Prescriptions criteria version two to identify potentially inappropriate medications, IBM Micromedex, to categorize potential drug-drug interactions as major and moderate. World Health Organization prescribing indicators were used to evaluate prescribing practices.

Results: The prevalence of potentially inappropriate medications in 275 prescriptions was 21.9%. Diclofenac was the most common inappropriate drug (n=23). Metoprolol is the second most inappropriate drug (n=12). Amlodipine and clopidogrel, aspirin and furosemide, and aspirin and spironolactone together accounted for 71.42% of major interactions (n=15). Atorvastatin and clopidogrel was the most common moderate drug-drug interaction in our study (n=24). The average number of drugs per encounter, the percentage of drugs with a generic name, and the percentage of drugs from the essential drugs list must be improved.

Conclusion: There is a need to provide awareness through education about the explicit criteria to identify potentially inappropriate medications and prescribing indicators that aid in rational prescribing in the elderly.