• Posted March 9, 2026

Common Drug Class Shows Links to Heart Risk -- Are You Taking One?

A common class of drugs called anticholinergics might boost risks for heart failure and other dangerous cardiac conditions, a new study says.

People taking the largest amounts of anticholinergic drugs had a 71% higher risk of heart health problems than those who didn’t use these drugs at all, researchers recently reported in the journal BMC Medicine.

The study couldn't prove cause-and-effect, but the association was particularly strong for heart failure and heart rhythm issues, Swedish researchers said.

“Our results indicate that the cumulative drug burden can affect heart regulation, not only in the short term but also over the long term,” senior researcher Hong Xu, an assistant professor of neurobiology, care sciences and society at the Karolinska Institute in Stockholm, said in a news release.

“This does not mean that the drugs should always be avoided, but that exposure should be monitored carefully,” Xu said.

Anticholinergic drugs reduce the effect of a neurotransmitter called acetylcholine, which serves a key role in how the nervous system functions.

These drugs are used throughout medicine: As sleep aids, antihistamines, urinary incontinence medications and certain antidepressants, the researchers explained in background notes.

Anticholinergics are available both by prescription and over-the-counter. For example, the popular pain medications Tylenol PM and Advil PM both contain the anticholinergic drug diphenhydramine.

For the new study, researchers tracked the health of more than 500,000 Stockholm residents aged 45 or older. None had any prior history of heart disease except for high blood pressure.

The team followed participants for up to 14 years, to see how anticholinergic drugs might affect their heart health.

“Many of these drugs are used by older people and by people with multiple medical conditions,” lead investigator Nanbo Zhu, a postdoctoral researcher at the Karolinska Institute, said in a news release. “We wanted to investigate whether the total exposure had any significance for the risk of developing cardiovascular disease over time.”

The researchers stressed that because this was an observational study, it could not draw a direct cause-and-effect link between anticholinergic drugs and heart problems.

It's possible that underlying medical conditions that affect people taking these drugs could be behind the increased heart risks.

Clinical trials will be needed to prove whether anticholinergic drugs directly impact heart health, Xu's team said.

More information

The Cleveland Clinic has more on anticholinergic drugs.

SOURCE: Karolinska Institute, news release, March 5, 2026