Heart Drug Interaction Linked to Sudden Death

Findings published in the February 2 issue of the Canadian Medical Journal have shed light on a potentially deadly combination of commonly prescribed drugs.  A widely used heart medication, Spironolactone (Aldcatone)  taken with the antibiotic trimethoprim-sulfamethoxazole (Septra, Bactrim) has been shown to raise blood potassium levels which can cause sudden death.

A study out of St. Michael’s Hospital in Toronto monitored more than 200,000 patients aged over 66 who were treated with the heart medication.  Over a period of 17 years, nearly 12,000 people died suddenly after taking trimethoprim-sulfamethoxazole or another antibiotic.  Most of those patients were over the age of 85.

Drug interaction and polypharmacy is a growing concern among the senior population.  According to a recent investigation by CBC’s Marketplace, many pharmacists across Canada may not be providing patients with important information on drug interactions.

Marketplace used hidden cameras to document counseling provided by pharmacists in 50 pharmacies across nine Canadian cities.  In more than half of the visits, potentially harmful drugs such as Tylenol 1 (with codeine) and iron supplements, were sold without any advice on possible interactions with other drugs.

Iron supplements such as Palafer can lesson the effect of some antibiotics and codeine, found in Tylenol 1, is both addictive and can interact with other drugs by increasing their effect.

With seniors taking multiple medications from different doctors, it is critical to keep a current list of medications and talk to a trusted pharmacist about possible interactions.  Fill medications from one pharmacy and review any changes in medications or dosages, including vitamins, supplements or alternative therapies with your primary physician. 

According to a 2013 case study published in the October 1 issue of the Canadian Medical Association Journal,  a thorough investigation of drug interactions and dosages can have an enormous effect on the “overall function and well-being of the patient.”

“Medications are potential contributors to geriatric syndromes such as falls and cognitive impairment.  Communication between health care professionals will improve medication selection and avoid doses that contribute to functional difficulties in older patients.”