Do not turn to these diet pills if you went crazy with the fruit cake.

The Food and Drug Administration are warning people to avoid 28 weight-loss products that contain unlisted and possibly dangerous ingredients that could land you in the emergency room.

"These tainted weight-loss products pose a great risk to public health because they contain undeclared ingredients and, in some cases, contain prescription drugs in amounts that greatly exceed their maximum recommended dosages," said Janet Woodcock, M.D., the director of FDA’s Center for Drug Evaluation and Research. "Consumers have no way of knowing that these products contain powerful drugs that could cause serious health consequences. Therefore FDA is taking this action to protect the health of the American public."

The FDA is considering criminal charges against the companies who have not responded to requests for recalls.

The 28 tainted products are:

Fatloss Slimming

2 Day Diet     

3x Slimming Power

Japan Lingzhi  24 Hours Diet

5x Imelda Perfect Slimming

3 Day Diet

7 Day Herbal Slim

8 Factor Diet

7 Diet Day/Night Formula

999 Fitness Essence

Extrim Plus

GMP

Imelda Perfect Slim

Lida DaiDaihua

Miaozi Slim Capsules

Perfect Slim

Perfect Slim 5x

Phyto Shape

ProSlim Plus

Royal Slimming Formula

Slim 3 in 1

Slim Express 360

Slimtech

Somotrim

Superslim

TripleSlim

Zhen de Shou

Venom Hyperdrive 3.0

Most of the diet pills listed above appear to be from China and are mainly sold on the Internet. Nearly all of the pills contain sibutramine, a powerful appetite suppressant that’s a chemical cousin of amphetamines. It can cause heart attacks, strokes and heart palpitations — especially in people with a history of heart problems or high blood pressure. The FDA lab found that some of these pills contained nearly three times the recommended daily dose. Several of the pills also contain the laxative-acting chemical, phenolphthalein, which is now being withdrawn from the market because of its cancer risks. The FDA also points out that they found traces of a drug not approved by the FDA, rimonabant, which has been associated with increased risk of depression and suicide.

If you’re using any of the weight-loss products listed above, the FDA advises you to stop taking those products and consult your health-care professional immediately. You can also report any serious side effects or product quality problems at FDA’s MedWatch Adverse Event Reporting system on the FDA’s website, or call 800-FDA-1088.

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