Drugs approved by FDA not always safe for all

Whether a medication's benefits outweigh potential risks will become an even greater issue as the population ages and the number of new formularies increases.

By Susan J. Landers, AMNews staff. Nov. 4, 2002.

Washington -- Although physicians and even some patients realize that no drug is 100% safe, they don't always focus on just how much is unknown about a drug even after it is approved by the Food and Drug Administration for use by the general population.

When a drug is approved, the FDA is saying, "the risk is reasonable given the potential benefit for the population that was studied and for the condition that was studied," said Nancy Smith, PhD, director of training and communications at the agency's Center for Drug Evaluation and Research.

Dr. Smith was speaking at a conference on medication safety held Oct. 17 in Bethesda, Md.

"Once a drug is on the market, you go from a population of a couple of thousand at most, to a population of millions of people who are taking these products. And things are going to show up that never could have been predicted in clinical trials," she said. While a large clinical trial may mean that a new drug is being tested on 2,000 to 3,000 people, an adverse event may show up only after 5,000 people use the medication.

After a drug is approved, it may be prescribed for patients who are older than participants in the trial or for patients who use additional medications. "We may be in an unknown area where we don't know if the benefits outweigh the risks," Dr. Smith said.

It's also possible that there may be more benefit and less risk carried by a new drug, but that is also an unknown, said Dr. Smith. While off-label use of a drug is certainly not discouraged, she said, physicians should be aware that such use means venturing into unknown territory. [...]