A recent Consumer Reports investigation shows America's drug-safety system is deeply flawed.

The report identifies a dozen widely prescribed drugs that are linked to rare but potentially serious reactions.

Consumer Reports said these drugs should be taken with caution, and in most cases only as a last resort.

"These prescription drugs have legitimate medical uses," said Consumer Reports Joel Gurin. "But there's also evidence that they carry serious risks. And those risks were underestimated or undetected when the FDA approved them."

The drugs and drug types with undetected or underestimated risks at the time of approval are sold under many names and include:

Celebrex, a pain reliever

Crestor for cholesterol

Depo Provera, a contraceptive

Elidel and Protopic for Eczema

Isotretinoin for severe acne

Lariam to prevent Malaria

Meridia for weight loss

Ovide for head lice

Premarin and other estrogens to treat symptoms of menopause

Serevent Diskus for Asthma

Zelnorm for irritable bowel syndrome

Zoloft, Effexor and other antidepressants, particularly when prescribed to young people.

With most of these drugs, Consumer Reports said the risks are rare, and a few are not conclusively proven, but they point to weakness in the nation's drug-safety system.

"The FDA is short-staffed and has tight deadlines to approve new drugs," said Gurin. "Once a drug is on the market, the FDA has only limited power to monitor it for safety."

If you have been prescribed one of the above drugs, Consumer Reports says don't stop taking it on your own. It might be the right medication for you, but be sure to talk to your doctor about the risks and whether there are better options.

Consumer Reports has a list of all the drugs mentioned on their Web site under the "Health & Fitness" section.