Heart Failure Patients Must Be Wary of Drug Interactions with OTC Products

A scientific statement from the American Heart Association (AHA) warns that unintended interactions among prescription drugs, OTC products, herbs, or nutritional supplements may trigger or worsen heart failure (HF).

The statement, published this month inCirculation, said certain medications can cause heart-related problems by:

• Being toxic to heart muscle cells or changing how the heart muscle contracts.

• Interacting with HF medications, which means some of their benefits are lost.

• Containing more sodium than advised for patients with HF.

A common problem with non-steroidal anti-inflammatory drugs like ibuprofen is that they can cause sodium and fluid retention, which in turn reduces to effectiveness of diuretics. OTC heartburn and cold medicines may have similar effects on HF patients, who are often restricted from consuming too much sodium.

“Patients have been taught to read food labels for sodium content, but they also need to read labels on over-the-counter medications and natural supplements,” said Robert L. Page II, PharmD, MSPH, chair of the writing committee for the new scientific statement.

Many common, natural ingredients interfere with one or more medications prescribed for HF, including green tea, danshen, hawthorn, ginseng, St. John’s wort, and ephedra. Ephedra is known to raise blood pressure.

The AHA noted that HF patients have 5 or more different medical conditions and take 7 or more prescription medications daily, on average. Pitfalls of this polypharmacy include increased risk of adverse drug events, drug-drug interactions, and medication nonadherence.

“Since many of the drugs heart failure patients are taking are prescribed for conditions such as cancer, neurological conditions, or infections, it is crucial but difficult for health care providers to reconcile whether a medication is interacting with heart failure drugs or making heart failure worse,” Dr. Page said. “…Ideally, there should be a ‘captain’ who oversees your medications. This person might be a physician, advanced practice nurse, nurse, or a pharmacist who is managing your heart failure.”

Clinicians are well positioned to review patients’ medication regimens to ensure that no offending drugs are listed. Their advanced knowledge of prescription and OTC medications, herbal supplements, and drug-drug interactions is a proven advantage for medical teams, and they effectively reduce polypharmacy.

In particular, clinicians should make sure patients are aware of the dangers contained in seemingly innocuous OTC remedies, herbs like St. John’s wort or ginseng, and even green tea.