Consumers concerned about the risks of swine flu should be skeptical of Web sites and e-mails that promote some so-called prevention products, including a "generic" substitute for prescription drug Tamiflu.

That's the latest warning from Hawaii's Better Business Bureau, which said that these scams are of particular concern as consumers may be putting their health at risk by taking medicine purchased from sites that don't require a prescription for prescription-only drugs.

"It's not surprising that the news coverage regarding the delay in delivery and current low inventory of H1N1 vaccine has inspired scammers to take advantage of the public's anxiety about the situation," said Dwight Kealoha, chief executive officer of Hawaii's BBB.

He cautioned that federal agencies have come across contaminated, counterfeit and counterproductive pharmaceutical products, including Tamiflu, a prescription drug used to treat H1N1 patients.

Kealoha said what was sold as the generic version of Tamiflu actually contained vitamin C and other substances that can neither treat nor prevent the H1N1 virus.

"At best, these products don't work. At worst, they're dangerous," Kealoha said. "They waste people's money but, more importantly, they might keep them from getting medically sound treatment."

He said he's not aware of particular cases of Hawaii victims but wants to send out the warning to help prevent such scamming.

There are so many supposed flu-prevention and flu-remedy products available online that the U.S. Food and Drug Administration created a "Fraudulent Products List" on its Web site.

In some cases, the product might be legitimate — such as an air purifier — but the FDA questions the marketing language and promised health benefits used to sell the product.

Other products listed include lotions and gels, gloves and masks, herbal extracts, sprays, body washes, inhalers, flu kits, supplements, tea and even a shampoo.

Hawaii's BBB offers some tips to help protect you from swine flu scams:

• Be wary of promotions using words such as "scientific breakthrough," "miracle cure," "secret ingredient" or "ancient remedy."

• Avoid Web sites that don't provide the company's name, physical address, phone number or other contact information.

• Don't fall for personal testimonials or claims that a product is a quick, effective way to treat or cure an illness. They may sound convincing, but are not substitutes for scientific proof.

• Follow health advice only from a trusted source, and don't believe product claims to prevent or cure swine flu.