It appears that drug giant Bayer HealthCare is illegally marketing two unapproved aspirin medications, the U.S. Food and Drug Administration (FDA) said in warning letters issued Tuesday.

Bayer Women's Low Dose Aspirin + Calcium and Bayer Aspirin with Heart Advantage are the unapproved drugs. In addition to being labeled as pain relievers, both products claim to reduce the risk of heart disease. Bayer Women's also claims to fight osteoporosis. Neither product has been approved by the FDA for such uses whatsoever. "The labeling in terms of directions is very confusing," says Dr. Marc Itskowitz, an internist at Allegheny General Hospital. "The aspirin is meant for short term use. But the calcium and the phytosteroids are meant for long term use."

The FDA warned the company that treatments for heart disease and osteoporosis must be reviewed by government scientists and cannot be sold over the counter. Doctors traditionally recommend aspirin to treat aches and pains and as a blood thinner for patients with heart disease.

But Bayer defended the medications by saying that no major negative reactions have been reported with the drugs. "We stand behind both products and all marketing claims made in their support," the German drug maker said in a statement. Moreover it’s their users’ obligation to read and follow the instructions inside the drug’s box before they start taking them.

It is a known fact that the agency allows traditional pain relievers to be sold over-the-counter without review, as long as they include standard directions and labeling for consumers. But the FDA said Bayer's products overstepped those regulations by claiming that the added ingredients in each medicine help fight specific diseases.