The use of daily low-dose aspirin to prevent a heart attack or stroke in those with no previous cardiovascular issues is being questioned by the U.S. Food and Drug Administration.

Although previous scientific evidence has shown that taking a daily dose of aspirin has helped to prevent a heart attack or stroke in some people, it doesn’t necessarily work for everyone. These daily doses can even cause unwanted side effects, including bleeding into the brain or stomach.

Additional care is needed when aspirin is taken in conjunction with other blood thinners, including rivaroxaban (Xarelto), dabigatran (Pradaxa) and apixiban (Eliquis).

Dr. Robert Temple, M.D., the FDA’s deputy director for clinical science, believes that individuals should take aspirin daily to prevent a heart attack or stroke only after speaking with a health-care professional who can accurately assess the benefits and risks.

“Since the 1990s, clinical data have shown that in people who have experienced a heart attack, stroke or who have a disease of the blood vessels in the heart, a daily low dose of aspirin can help prevent a re-occurrence,” said Temple in a statement.

After closely analyzing data from various studies, the FDA concluded that there is no solid evidence to support the use of aspirin as a preventative measure by those who have never suffered a cardiac episode. The health benefits of such “primary prevention” has not been established, with health risks associated with this practice still present.

There are currently various ongoing clinical investigations being conducted that are continuing to evaluate the use of aspirin for primary prevention of heart attack or stroke. These studies are being monitored by the FDA.