The U.S. Food and Drug Administration has started listing on its Web site drugs being evaluated for potential safety issues, the agency said Friday.

“If a drug appears on a quarterly report, it means we have begun analysis to determine whether there is a safety problem that requires further evaluation,” Dr. Gerald Dal Pan, director of the FDA’s Office of Surveillance and Epidemiology, Center for Drug Evaluation and Research, said during a Friday teleconference.

This information is being posted as part of the 2007 Food and Drug Administration Amendments Act. Under the act, the agency must post quarterly information on potential drug risks, based on the agency’s review of adverse-event reports submitted by doctors.

The list contains only the drug’s name and the potential problem associated with it; it doesn’t reveal the extent of the problem or how many adverse reports have been filed.

The list also doesn’t include all the drugs the FDA is currently reviewing for safety problems, Dal Pan said. “This list is derived from issues identified in the adverse-event reporting system,” he said.

The current list covers January to March 2008. The appearance of a drug on the list doesn’t mean the FDA has concluded that there’s a problem with it. A drug only appears on the list because the agency has identified a potential safety problem, Dal Pan said.

The initial list, released Friday on the Web site, includes 20 drugs. The drugs range from the anesthetic Desflurane, which has been linked to cardiac arrest, to nitroglycerin (Nitrostat) which is used to treat angina. A confusing label could result in overdose, the agency said.

Other drugs on the list include natalizumab (Tysabri), which is used to treat multiple sclerosis and Crohn’s disease and has been linked to melanoma, and telbivudine (Tyzeka), which treats hepatitis B and has been linked to damage to the nervous system, the FDA said.

Drugs under investigation before 2008 or after March aren’t included on the current list. Dal Pan said he wasn’t sure when an updated list would be posted.

FDA officials emphasized that people taking drugs on the list should not overreact and stop taking them.

“As always, we are very sensitive to the potential misinterpretation or over-interpretation of any potential unintended consequences because the drug is on the list,” Dr. Paul Seligman, the associate director of Safety Policy and Communication at the FDA’s Center for Drug Evaluation and Research, said during the teleconference.

“There is always the risk that anytime you put something in writing and post it on an official FDA Web site that people will read into it more than that we are just conducting a review,” Seligman said. “We are expecting people not to take actions simply based on the fact that we are evaluating a particular drug.”

In addition to providing the public with more information, the agency thinks the list will encourage more reporting of adverse events.

For more on drugs under review, visit the U.S. Food and Drug Administration Website.