For the elderly, antidepressants may cause adverse, synergistic effects with other drugs

Physicians should exercise extra caution when prescribing antidepressants for older patients since they could negatively react with or cause adverse side effects when combined with other drugs, finds a new study by Thomson Reuters, the University of Southern California, Sanofi Aventis and others, published in the American Journal for Geriatric Psychiatry. Analysis of prescription records of more than 39,000 health claims for patients 65 years and older who began taking antidepressants between 2001 and 2006 showed that more than a quarter of patients were prescribed the antidepressants with other medications that could cause a major interaction, while another 36 percent had potential for moderate interactions. Side effects, including insomnia, somnolence, drowsiness and dizziness, caused many elderly patients to discontinue the use of antidepressants, and only 45 percent of those with documented side effects refilled their prescriptions.

ACSH's Dr. Gilbert Ross sympathizes with geriatricians since many older patients suffer from the matched effects of reduced organ function, greater susceptibility to minor alterations in physiology and slowing brain function that may contribute to the risk of mixing-up medications. “When I used to treat elderly patients, I would request that they bring in all of their medications in a brown bag, and often times, you find drugs you had no idea they were taking because other physicians or providers had prescribed them. By neglecting to inform their primary caregivers about these, usually unintentionally, older patients place themselves in harm’s way — potentially experiencing devastating interactions and side effects from all of these combined medications.”

What’s the bottom line? “You have to be very careful and thorough when treating elderly patients, especially since older antidepressants can have serious side effects compared to newer SSRI’s,” says Dr. Ross. “Further, family members should try to check up on their senior relatives and help them to take their medications correctly, and not share or trade pills with their friends and neighbors — another common problem among the elderly.”