Manufacturers of audiotapes, herbal remedies, even sunglasses, are using the flimsiest links to Viagra to make money from the craze.

... Viagra's manufacturer, Pfizer, is getting tough on companies flouting trademark laws

The Las Vegas-based BluBlocker Corp. says its BluBlocker Viagra shades help mask the blue tinge that Viagra adds to some users' vision.

"This is crass commercialism," concedes BluBlocker chairman Joseph Sugarman. "I just couldn't resist the opportunity to tie in with that product."

Others take advantage of other side effects of the impotence cure. Bradley Pharmaceutical sells one vaginal lubricant with the slogan "What Viagra does for him, Lubrin does for her."

Bradley executives say it is not them who have made the connection ... but consumers. Since the introduction of Viagra they have noticed a jump in sales, which they attribute to the drug - or more precisely, an increase in the number of ageing women who are dealing with reinvigorated Viagra users.

Marketing vice president Gene Goldberg hopes to ride the trend by introducing a new liquid lubricant months ahead of schedule.

Enthusiasm dampens

Some companies are clearly flouting trademark laws, and Pfizer Inc. - the maker of Viagra - is fighting back.

"We expect there will be copycats or attempts at coat-tail marketing," spokesman Andy McCormick says. "When they step over the line in terms of the law, we will step in."

That has already happened in three cases, says Nels Lippert, an attorney for Pfizer.

Blublocker's Mr Sugarman says he will probably give away the 200 pairs already made, after Pfizer lawyers threatened a lawsuit. He says: "That kind of dampened our enthusiasm."

Two other companies have run afoul of Pfizer attorneys since Viagra was approved for sale on March 27. Both sell herbal supplements over the Internet and were promoting sexual potency products with extremely similar names: Vaegra and Viagro.

"They've capitulated," after being hit with trademark infringement suits, Mr Lippert says.

It's all in the mind

Some believe they can get the message across without using a drug. A maker of audiotapes with subliminal messages, HypnoVision Inc., has dozens of orders for its mood-enhancing tape. In light of recent events, it has been reworked to include messages like "My body works perfectly during sex because my Viagra is working."

And Durex, the world's top condom maker, says sales began climbing slightly about five weeks ago as pharmacists started stocking Viagra.

Others experienced more dramatic improvements in their performance. Condom Express, which distributes condoms and "intimate lubricants" over the Internet, says sales of both more than doubled since March, when hype about Viagra's anticipated arrival began.

"I don't know if it's from Viagra," company president Bruce Gasparre says. "It's quite possible."