Penis enlargers and constricting rings to maintain erections can be seized at U.S. borders, U.S. regulators said Thursday, citing inadequate safety labels.

The devices have inadequate directions for use and can have harmful effects, from rupturing blood vessels to causing gangrene of the penis, the Food and Drug Administration said in guidance to import inspectors posted on the agency’s Web site. The guidance was a revision to guidelines on "external penile rigidity devices" the FDA published in 2004.

“Basically, the labeling of these devices falsely states or implies they will treat impotence, prolong erection, and increase the dimensions of the penis,” the FDA said in the new notice.

The FDA said such devices fall into several categories:

Mechanical stretching devices, which "employ weights or lines tied to other parts of the body such as the knee, to affect tension on the penis.

Vacuum operating devices, "those employing a sealing principle in the area of the base of the penis and an evacuation mechanism to drop the atmospheric pressure around the penis, thereby affecting increased blood flow."

Constrictive rings, which "constrict the base of the penis after erection has been achieved and cause the erection to be maintained by blocking the normal circulation of blood from the penis."

Supportive devices, which "function as a splint or cradle in order to maintain a resumblance of turgidity."

Source: [Star-Telegram]