What is polypharmacy and why is it important?

Medication is by far the most common form of medical intervention for many acute and chronic conditions. Drug therapy can be highly effective in preventing disease or slowing disease progression, with guidelines for single diseases recommending the use of a variety of evidence based drug treatments. However, there is often a mismatch between prescribing guidelines for specific medical conditions and the range of clinical complexity found in individuals. For complex patients with multiple conditions; frailty; a dominant condition (e.g. dementia) or approaching the end of their lives, the implementation of the sum of evidence based recommendations may not be rational, may increase the risk of adverse drug events and may not align with the patient’s preferences.

The term polypharmacy itself just means “many medications” and is defined to be present when a patient takes two or more medications. It is recognised that polypharmacy is often beneficial. For example, secondary prevention of myocardial infarction requires the use of at least four different classes of drugs (antiplatelets, statin, ACE inhibitor, beta blocker).

Appropriate polypharmacy requires consideration at any point of contact involving medication but there are five clear stages which should be used as a trigger to do this:

  1. Prescribing (and risk assessment)
  2. Medication review
  3. Dispensing and administration
  4. Communication and patient engagement
  5. Medication reconciliation (at care transitions)

Although Polypharmacy Guidance, Realistic Prescribing 2018 concentrates on the holistic patient-centred medication review, the principles, tools and recommendations can be used at any stage, especially at the point of prescribing.

Appropriate polypharmacy

Present, when: (a) all drugs are prescribed for the purpose of achieving  specific  therapeutic  objectives  that  have  been  agreed  with  the  patient;  (b) therapeutic objectives are actually being achieved or there is a reasonable chance they will be achieved in the future; (c) drug therapy has been optimized to minimize the risk of ADRs and (d) the patient is motivated and able to take all medicines as intended.

Inappropriate polypharmacy

Present, when one or more drugs are prescribed that are not or no longer needed, either because: (a) there is no evidence based indication, the indication has expired or the dose is unnecessarily high; (b) one or more medicines fail to achieve the therapeutic objectives they are intended to achieve; (c) one, or the combination of several drugs cause inacceptable adverse drug reactions (ADRs), or put the patient at an unacceptably high risk of such ADRs, or because (d) the patient is not willing or able to take one or more medicines as intended.