Enzyte is an American herbal nutritional supplement originally manufactured by Berkeley Premium Nutraceuticals. The marketing of Enzyte resulted in a conviction and prison term for the company's owner and bankruptcy of the company. The product is now marketed by Vianda, LLC of Cincinnati, Ohio. The manufacturer has claimed that Enzyte promotes "natural male enhancement," which is a euphemism for enhancing erectile function. However, its effectiveness has been called into doubt and the claims of the manufacturer have been under scrutiny from various state and federal organizations. Kenneth Goldberg, medical director of the Male Health Center at Baylor University, says, "It makes no sense medically. There's no way that increasing blood flow to the penis, as Enzyte claims to do, will actually increase its size."

In March 2005, following thousands of consumer complaints to the Better Business Bureau, federal agents raided Berkeley facilities, gathering material that resulted in a 112-count criminal indictment. The company's founder and CEO, Steven M Warshak, and his mother, Harriet Warshak, were found guilty of conspiracy to commit mail fraud, bank fraud, and money laundering, and in September 2008 they were sentenced to prison and ordered to forfeit $500 million in assets. The convictions and fines forced the company into bankruptcy, and in December 2008 its assets were sold for $2.75 million to investment company Pristine Bay, which continued operations.

Enzyte is widely advertised on U.S. television as "The once-daily tablet for natural male enhancement", or "The one-a-day tablet for natural male enhancement." The commercials feature a character known as "Smilin' Bob," acted out by Canadian actor Andrew Olcott, who, in the commercials, always wears a smile that is implied to result from the enhancing effects of Enzyte; these advertisements feature double entendres. Some such commercials also feature an equally smiling "Mrs. Bob."

Because Enzyte is an herbal product, no testing is required by the U.S. Food and Drug Administration. An official of the Federal Trade Commission division that monitors advertising says the lack of scientific testing is "a red flag right away. There's no science behind these claims." The company has conceded that it has no scientific studies that substantiate any of its Enzyte claims.

Ira Sharlip, a spokesman for the American Urological Association, has said, "There is no such thing as a penis pill that works. These are all things that are sold for profit. There's no science or substance behind them."

Enzyte's formulation was reportedly developed for Vianda by Marilyn Barrett.^{[citation needed]}

Enzyte is said to contain:^{[citation needed]}

Most of the above ingredients are commonly available as over the counter herbal or dietary supplements, and most have anecdotal reports, but marginal or unproven scientific evidence, of efficacy on various systems in the human body. Several of the herbal ingredients are included only in very low quantities.