Prevalence of polypharmacy and risk of potential drug-drug interactions among hospitalized patients with emphasis on the pharmacokinetics.

Background: Both polypharmacy and potential drug-drug interactions (pDDIs), especially those at the pharmacokinetic level, are common in hospitalized patients and are associated with adverse effects and failure of therapy.

Objective: The aim of the present study is to investigate retrospectively the prevalence of polypharmacy and the risk of potential pharmacokinetic drug-drug interaction among hospitalized patients.

Methods: The medical documentation of hospitalized patients in the unit of internal diseases at the hospital "St Marina" in Varna, Bulgaria for a period of six months (January-July 2016) was retrospectively reviewed.