NEW YORK (Reuters Health) - Official reports of negative reactions to prescription drugs have increased dramatically over the last decade, according to a new study.
In a U.S. Food and Drug Administration (FDA) database launched in 1969, researchers found that over half the reports of "adverse events" suspected to be caused by a particular drug or device date from just the past 10 years.
The FDA currently receives about half-a-million such reports of health problems, and even deaths, associated with medical products each year. In 2000, they came in at a rate of nearly five for every 10,000 office visits in which at least one prescription was written. By 2005, that rate had risen to nearly seven per 10,000 visits, according to the new analysis published in the Archives of Internal Medicine.
Between 2000 and 2010, the number of reports coming in grew steadily by more than 11 percent every year. By 2010, they added up to 2.2 million reports -- 55 percent of the entire database total.
Study author Dr. Sheila Weiss-Smith of the University of Maryland in Baltimore cautioned that the number of reports does not equal the true number of negative reactions to drugs.
Manufacturers are required to report to the FDA any health problem they suspect stems from one of their products, but for doctors, patients, lawyers, and anyone else who reports these reactions, it's entirely voluntary, she told Reuters Health.
It's hard to estimate how many negative reactions to drugs actually occur, Weiss-Smith noted. Some experts suggest official reports represent one-tenth of the number of actual negative reactions, but she said she doesn't trust that figure. "We just don't know. We don't know what percentage of events actually gets reported."
She added that it's also difficult to determine why the reports are increasing. The elderly now make up a larger percentage of the population, and they may be more likely to react negatively to drugs, she speculated.
More people are taking drugs, and for longer times, which increases the potential for bad reactions, and negative interactions between drugs, she said.
Often, the number of reports will increase for a particular drug after news articles appear that say it has problems - for instance, the pain reliever Vioxx, which was removed from the market in 2004. "It's amazing how publicity spurs reporting," she said.
Weiss-Smith and her collaborators reviewed all official reports of negative reactions to brand-name drugs submitted between 2000 and 2009.
During that period, the FDA received 2.2 million entries to its Adverse Event Reporting System (AERS). Among reports that included information about what happened to the patient, more than 40 percent were hospitalized and 15 percent died.
Some of the drugs most frequently tied to negative reactions were in a new class known as recombinant DNA products, including some treatments for autoimmune diseases such as rheumatoid arthritis and Crohn's disease. By acting on the immune system, these drugs leave people at greater risk of infections.
Other drugs that topped the list were a diabetes treatment (Byetta), one for osteoporosis (Forteo), as well as a birth-control patch (Ortho Evra).
Negative reactions can occur from a variety of drugs, and patients need to take steps to protect themselves, Weiss-Smith urged. "Drugs are chemicals. And you're putting something in your body. You need to know what it is." She recommended that everyone tell their doctors what they are taking, and try to go to one pharmacy, "so someone can keep track of all the different things," preventing negative interactions.
If you keep adding drugs to your daily routine, talk to your doctor about whether you can cut back on others, so that you are only taking the minimum necessary amount, she said. Read all the material that comes with medicines, and tell someone immediately if you start to feel unwell. "If something doesn't feel right, talk to your doctor, talk to your pharmacist."
SOURCE: bit.ly/7qXyI Archives of Internal Medicine, online March 28, 2011.