The life expectancy is constantly increasing in developed countries, partly due to improved medical care. On average, every senior in Germany > 60 years of age is taking three or more medications per day, increasing risk for developing side effects due to polypharmacy (Moßhammer et al. 2016). Little is known about interfering effects of drugs on selenium (Se) metabolism and selenoprotein expression. Certain examples have been identified, e.g. statins affecting tRNA-Sec maturation (Moustafa et al. 2001) and aminoglycosides altering selenoprotein P (SELENOP) expression in HepG2 cells (Renko et al. 2017), causing a replacement of selenocyseine by other amino acids.