We recently came across a great video to introduce this subject.
Bohemian Polypharmacy on Youtube
A good review article on this topic is: How polypharmacy has become a medical burden worldwide. “Taking a multitude of medicines, whether they are prescription drugs, OTC treatments, herbal or dietary supplements — known as polypharmacy — is not only a burden for patients, it can be dangerous. We need a way to mitigate the danger of unwanted drug interactions and improve drug adherence to essential medicines, and this is as true for the United States as it is in Europe. It is imperative that patients are empowered to make informed decisions about the medicines they are taking, and pharmacists and other healthcare professionals have an important role in educating patients to make these decisions.”