Medication Side Effects and Interactions
Because of their high rate of medication use, older adults also have the highest risk of adverse drug effects (Kane et al., 1994). In part, these problems result from physiological changes that occur with age in how drugs are absorbed into the body, how long they remain, and how well they work. For example, changes in the stomach may slow down the rate at which drugs enter the body, meaning that
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achieving the effective level of the drug in the body may take longer. Changes in liver and kidney functioning affect how rapidly the drug is removed and excreted from the body, meaning that levels of the drug may remain high for longer periods of time.
As we have seen, age-related increases in the frequency of chronic conditions means that older adults are likely to have more than one medical problem for which they take medications. In this regard, Lucy is fairly typical. Treating multiple conditions results in polypharmacy, the use of multiple medications. Polypharmacy is potentially dangerous because many drugs do not interact well; the action of some drugs is enhanced in combination with others, whereas other drugs may not work at all in combination. Drug interactions may create secondary medical problems that in turn need to be treated, and the primary condition may not be treated as effectively. Moreover, drug interactions can produce symptoms that appear to be caused by other diseases; in some cases they may cause confusion and memory loss that mimics Alzheimer’s disease. Professionals and family members need to monitor the situation closely (Arnold, 2008).
Lucy’s daughter is correct in worrying about her mother taking her medications as prescribed. Analyzing a person’s medication regimen, including both prescription and over-the-counter medications, and asking the patient or caregiver to describe how they are taken is important in diagnosing
health problems. Given the high level of medication use among older adults, what can be done to minimize drug interaction effects? Physicians play a key role, but other health care professionals also must be alert because older adults typically go to more than one physician. Accurate medication histories including all types of medicines are essential. Inappropriate use of drugs, such as antipsychotics to control behavior, must also be monitored.