We are seeing increasing numbers of older people with cancer presenting to our clinics for chemotherapy. Many of the general elderly population have chronic medical conditions such as hypertension, high cholesterol, reflux, cardiovascular disease or arthritis and may take medications for these. Also it is not uncommon for people to be taking self-prescribed over-the-counter preparations, or complementary and alternative medicines, and they may or may not think to mention this when starting chemotherapy. Commencing typical chemotherapy with one or more cytotoxic or targeted agents, in addition to drugs to prevent side effects or treat existing symptoms, may lead to polypharmacy.¹ 

Recent studies from different parts of the world have identified that polypharmacy is common in older cancer patients, with some taking up to 17 different medications.²  This presents us with new challenges. We must identify what our patients are actually taking in order to avoid or manage potential new adverse effects or drug interactions. Various methods and tools are avaliable for structured medication assessment of all prescription, over-the-counter and CAM, identification of any inappropriate medication use and/or adverse consequences. Implementing these processes in the busy out-patient chemotherapy settings can be a huge challenge. The next step is screening either all patients or those at high risk for drug interactions. Accurate drug interaction information is pivotal in helping clinicians to make sound clinical decisions when starting or chaning cancer treatments. Whether drug combinations produce clinically significant adverse effects is essential information, and some drug interaction references provide ratings of severity and scientific evidence of interacting drugs. Ideally where possible or necessary, rationalisation of prescribed medications is logical, and this is best achieved in consultation with the patient (and/or family or carer) and other prescribers.

The challenge of polypharmacy in older cancer patients is best managed by a multi-disciplinary team approach.