Many older adults use multiple medications and over-the-counter medications to treat an illness. As a result they may use more medications than are clinically necessary. In addition many patients visit different health care medical specialists for different ailments and the particular specialist may be unaware of the other medications the patient is taking which can contribute to over medication.

In addition, many chronic diseases require more than one drug for effective treatment. For example, treatment regimens for high blood pressure may require taking two or three drugs. Other common diseases that require multiple drug treatments include heart disease, arthritis, visual impairment, diabetes, chronic pain, and lung disease. Given that a patient may suffer from any number of these illnesses, the total number of medications taken can escalate quickly.

For every additional unnecessary medication that is taken, the risk of a side effect increases exponentially. Compliance also becomes exceedingly difficult as the number of medications an older adult has to take on a daily basis increases. For example an older adult may be prescribed certain medications that need to be taken on an empty stomach while another medication may need to be taken with food. This means that the older adult may need to take a pill at six different times during the day. In addition, when an older adult suffers an adverse reaction, such as a rash, a new medication such as diphenhydramine (Benadryl) may need to be taken to treat the adverse effect that further perpetuates the polypharmacy. To avoid unnecessary medications, the older adult's medication regimen should be evaluated frequently for therapeutic effect, adverse effects and toxicity.

Since older adults often have many different medical specialists, it is recommended that the primary care provider coordinate all aspects of drug therapy for the patient. The patient should also have one pharmacy fill all of his prescriptions so that the records are in one place. The pharmacist can then screen the prescriptions and alert the older adult about any medication problems.