Polypharmacy is the concurrent use of multiple medications (often defined as more than five concurrent medications). Polypharmacy is a concern as it increases the risk of adverse drug reactions and drug-drug interactions, as well as resulting in decreased adherence to clinical guidelines. Symptoms secondary to adverse drug reactions and drug-drug interactions may be misdiagnosed as somatic symptoms, or cause additional complications, leading to yet further prescription of medications.

Our department has developed an algorithm (MERIS, MedicinRisikoScore) for identifying patients at high risk of medication errors. MERIS has been validated for use in both the emergency care setting and in general internal medicine departments. This project has been a collaboration with the Hospital Pharmacy, Region Midtjylland, and the Emergency Department, Aarhus University Hospital. MERIS is currently being further developed and validated for implementation in general practice, as well as part of the National Electronic Medication Chart (Fælles Medicin Kort) in collaboration with the Research Unit for General Practice, Aarhus University. 

Detection of Patients at High Risk of Medication Errors: Development and Validation of an Algorithm. Saedder EA, Lisby M, Nielsen LP, Rungby J, Andersen LV, Bonnerup DK, Brock B. Basic Clin Pharmacol Toxicol. 2016 Feb;118(2):143-9.

Classification of drugs with different risk profiles. Saedder EA, Brock B, Nielsen LP, Bonnerup DK, Lisby M. Dan Med J. 2015 Aug;62(8):A5118.

Number of drugs most frequently found to be independent risk factors for serious adverse reactions: a systematic literature review. Saedder EA, Lisby M, Nielsen LP, Bonnerup DK, Brock B. Br J Clin Pharmacol. 2015 Oct;80(4):808-17.