The FDA also instructed employees to block imports of the supplements, calling them "dangerous ... and even life-threatening." The agency said the supplement bears the name Yilishen when it is imported from China and is sold as Actra-Rx within the United States.

Laura Alvey, an FDA spokeswoman, declined further comment saying the matter is under investigation that may lead to criminal or civil enforcement actions.

Actra-Rx and Yilishen are promoted on Web sites as erectile dysfunction treatments that enhance men's sexual performance, the FDA said.

Despite an all-natural label, Actra-Rx capsules contain prescription strength levels of sildenafil, the active drug ingredient in Viagra, according to a letter published in the Journal of the American Medical Association.

Viagra, produced by Pfizer, was approved by the FDA to treat erectile dysfunction. The recommended dose is 50 milligrams. Some men take as little as 25 mg. or as much as 100 mg.

According to "Sex, Lies and Niagra," published in the Feb. 4, 2004 issue of JAMA, chemical analyses found an average of 55 milligrams of sildenafil per capsule of Actra-Rx and Niagra Actra-Rx, another name under which the product has been sold.

"The use of such nonprescription substances may present health risks for individuals with contraindications to the use of sildenafil," wrote the authors.

Follow up testing by the FDA confirmed Actra-Rx contained prescription-strength levels of sildenafil.

A spokesman for Los Angeles-based Body Basics declined comment. The company's voicemail identifies them as manufacturer of Actra-Rx. The company's Web site continues to advertise Actra-Rx as a "natural sexual enhancer" available in starter kits of 10 pills for $78.99.

In June 2003, Pfizer filed a trademark infringement suit against Body Basics, which had been using the name Niagra to sell the supplement. The federal court, in a consent judgment, barred the company from using that name, said Bryant Haskins, director of corporate media relations - http://www.channel4.com/news/relations at Pfizer.

When the FDA in March 27, 1998 approved Viagra, the first pill to treat impotence, it warned consumers not to use the drug in combination with products containing nitrates to avoid worrisome lowering of blood pressure.

According to the FDA, the sildenafil in Actra-Rx also can interact with certain prescription drugs that contain nitrates or nitrates in illicit substances, significantly lowering blood pressure to unsafe levels.

Men at risk include those with diabetes, high blood pressure, high cholesterol or heart disease. Those individuals use medications that contain nitrates and often suffer erectile dysfunction.

The FDA advised people who have taken Actra-Rx or Yilishen to stop using it and 상주출장마사지 - https://www.toptopanma.com/%ec%83%81%ec%a3%bc%ec%98%a4%ed%94%bc%ea%b1%b8... to consult a doctor regarding an alternate erectile dysfunction treatment.