Polypharmacy means taking several medicines regularly, usually four or more. A recent issue of the Journal of the American Medical Association noted, “Between 2015 and 2025, approximately 63 serious adverse events attributed to drug-drug interactions were reported to the US Food and Drug Administration among adults aged 65 years or older, 10% of which were fatal.” (Older people have slower drug metabolism and more chronic conditions, plus they see more specialists prescribing medications and use more OTC drugs and supplements.)
Here are the drug combinations rated the most dangerous:
- Blood thinners, such as Warfarin, taken with NSAIDs (non-steroidal anti-inflammatories, such as Aspirin and Advil), can dramatically increase the risk of internal bleeding.
- Blood pressure medications, such as Lisinopril, taken with diuretics, such as hydrochlorothiazide, plus NSAIDs, is a “triple whammy” that can cause acute kidney injury.
- Opioids, such as tramadol, taken with Benzodiazepines, such as lorazepam, can slow breathing and cause respiratory depression, confusion, falls, and overdose.
- Antidepressants, such as Zoloft, taken with supplements, such as St. John’s Wort, can trigger serotonin syndrome—a buildup of serotonin, the symptoms of which can be mild (shivering and diarrhea) to severe (muscle rigidity, fever and seizures), to death.
- Statins, such as Lipitor, taken with certain antibiotics, such as erythromycin, can cause muscle breakdown and kidney damage.
- Diabetes medications, such as insulin, taken with beta-blockers, such as metoprolol, can hide symptoms of low blood sugar, making hypoglycemia harder to detect.
- Anticholinergics, such as Benadryl, taken with sedatives, such as sleep aids, can increase the risk of confusion, falls, memory problems, and delirium.
- Multiple OTC cold and flu products taken together can cause liver damage. Examples of risky combinations include NyQuil plus Tylenol; DayQuil plus cough syrup; anything containing acetaminophen.
The intended audience for this article is doctors. I would
have hoped that they already knew about these interactions.
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