Multiple Medications May Worsen Health, Scientists Say

Older adults can end up taking one medicine to manage the unwanted effects of another. This pattern, called a prescribing cascade, may begin when a drug reaction is interpreted as a new health problem. Researchers examining records from more than 2 million older adults in Ontario found 24 common cascades that could be inappropriate. The starting prescriptions often included medicines for cholesterol or blood pressure, as well as iron, steroids, antidepressants and cholinesterase inhibitors used for dementia.

Examples show how quickly a regimen can grow. Constipation after taking iron may result in a laxative prescription. Muscle discomfort linked with cholesterol drugs may prompt pain treatment, while wakefulness associated with certain dementia medicines may lead to sleep medication. Such combinations are not necessarily unsuitable, according to Sonia Amin Thomas, Pharm.D., but a health professional should assess whether each drug is being used appropriately.

Taking too many medicines can raise the likelihood of interactions, dizziness, falls, confusion, hospitalization and other unwanted effects. It may also increase expenses and make treatment schedules harder to manage. Maryann Amirshahi, Pharm.D., M.D., notes that older adults may be especially sensitive to drugs. Reduced kidney function can allow medicines to build up to potentially toxic levels. Risk can also rise when several specialists do not share prescription information, or when cognitive problems make it difficult for a patient to communicate a complete medication history. Providers can respond to new symptoms by reviewing every medicine before adding another, then considering whether an existing drug should be adjusted or replaced. Pharmacists can help identify possible interactions, while records of medicines, supplements, dose changes and symptom timing can help clinicians connect a reaction to its possible source.