Updated

The Food and Drug Administration is cracking down on sex supplements again, warning the public on Monday about six products that were found to contain hidden drugs.

The names of the tainted products are: Reload, Get It Up, Super Cheetah, Cave Diver, Nights to Remember and X Zen Platinum. All of the products are marketed for sexual enhancement, and sold on various websites and in some retail stores, the FDA said.

All of the products were found to contain the drug sildenafil (sold under the brand name Viagra), and one was found to contain tadalafil (brand name Cialis). Sildenafil and tadalafil are prescription drugs used to treat erectile dysfunction. Sex supplements are not allowed to contain prescription drugs, and the drugs are not included on the products' labels.

Undeclared drugs in supplements are dangerous because consumers ingest these drugs without being told about their risks. Sildenafil and tadalafil can cause adverse reactions, including dangerously low blood pressure, if taken along with other prescription drugs that contain nitrates, the FDA says. (Some drugs prescribed to treat chest pain and heart disease contain nitrates.)

Consumers who take the products listed in today's warnings should stop using them immediately, and throw them away, the FDA says.

Last month, the FDA recalled two sex supplements, called Vicerex and Black Ant, because the products contained sildenafil and tadalafil. Earlier this year, the FDA warned consumers that several other sexual enhancement supplements contained undeclared drugs.

Because the FDA is unable to test and identify all tainted sexual enhancement products, consumers should exercise caution before buying any products in this category, the agency said.

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