June 2, 2005 -- -- Ever since Viagra exploded on the market eight years ago, it's been almost impossible to watch television without seeing ads for drugs designed to enhance a man's sexual experience.
The popularity of these pharmaceuticals has spawned a whole new line of natural male enhancement products. And they are among the hottest-selling products in the $26 billion herbal supplement -- or as the makers call them, nutraceutical -- industry.
Many of these products suggest extraordinary results. For example, four years ago, Berkeley Nutraceuticals, the largest seller of male enhancement pills -- said its Enzyte product would grow your penis up to 41 percent.
Recently, the company moderated those claims, and they now simply promise firmer, fuller-feeling, better-quality erections
Consumer advocate, Dr. Sydney Wolfe, says that with respect to the growing industry of natural male enhancement products, safety is unknown and effectiveness is unproven. "You've got an industry that just can invent something, grind up some root, put it in a bottle, [and] sell it," said Wolfe, author of "Best Pills, Worst Pills."
"Primetime Live" tested some Enzyte it purchased in March. The ingredients listed in the product packaging were found in the pills, including ginseng root, ginko biloba and saw palmetto.
Supplement makers say the product's ingredients have been used as sex enhancements for centuries, but Dr. Franklin Lowe, a leading New York urologist expressed serious doubts about whether any of them could enhance male sexuality.
"It's very enticing. It's good marketing. But to my knowledge, there's no clinical evidence that supports any of those claims," he said.
The manufacturer of Enzyte told ABC News that it had recently changed the formulation and that the product continues to work as advertised.
Still, the popularity of such products has created overnight millionaires -- like Michael Consoli and his nephew Vincent Passafiume, whose company C.P. Direct sold a male enhancement product called "Longitude."