Marketing claims made about one of its colon supplements is creating tension between Bayer Corporation, the American subsidiary of giant aspirin manufacturer Bayer AG, and the United States Department of Justice.

The DOJ Friday filed a motion to show cause why Bayer shouldn't be held in contempt for violating a 2007 court order issued in connection to the case United States v. Bayer Corporation -- which prohibits the drug company from making unsubstantiated claims for any dietary supplement it promotes or sells.

The government alleges Bayer promotes one of its products, Phillips' Colon Health, with claims about the product's purported benefits without presenting evidence to back up those claims, according to an agency news release.

According to the court order, the company is expressly barred from making any claim about the performance or efficacy of any dietary supplement, multivitamin or weight-control product unless Bayer, at the time such a claim is made, possesses "competent and reliable scientific evidence" to support the claim.

In the latest filing, the United States argues that when Bayer claims Phillips' Colon Health can "defend against" occasional constipation, diarrhea, and gas and bloating, it's actually implying the supplement "prevents, treats and cures" all of the aforementioned conditions, although "the company lacks competent and reliable scientific evidence for those claims," the DOJ release explained.

"Bayer is required to abide by a longstanding court order to back up claims it makes about the products it sells," said Assistant Attorney General Stuart F. Delery for the department's Civil Division. "The Department of Justice will not tolerate companies that seek to gain an unfair advantage over their competitors by promoting to consumers unsubstantiated claims about the health benefits of their products."

The DOJ motion asserts that, even though Bayer lacks the necessary evidence to support claims of the product's purported benefits, consumers have paid hundreds of millions of dollars for Phillips' Colon Health, for which the company runs a multimillion-dollar nationwide marketing campaign that includes print advertisements and television commercials featuring "The Colon Lady."

In 2007, the United States filed a civil complaint that alleged Bayer marketed its One-A-Day WeightSmart multivitamin and dietary supplement with unsubstantiated claims -- among other things, that the supplement helped prevent some of the weight gain associated with a decline in metabolism in users over the age of 30.

In order to resolve the complaint's allegations, Bayer agreed to pay a $3.2 million civil penalty and promised it would not make unsubstantiated representations regarding the benefits, performance, efficacy, safety or side effects of any dietary supplement, multivitamin or weight-control product.

The Consumer Protection Branch of the Civil Division and the U.S. Attorney's Office for the District of New Jersey filed the motion for contempt with the assistance of the Federal Trade Commission (FTC). The matter is filed as United States v. Bayer Corporation, No. 07-0001, in the District of New Jersey.