Newer drugs are not always better or safer. They are promoted more vigorously, and patients and doctors often request them thinking a more recent drug must be an improvement.
But a 2002 study of more than 42,000 patients found that generic diuretics were not only cheaper than newer drugs, but also more effective at lowering blood pressure.
Treating high blood pressure with generic diuretics could save the U.S. health care system as much as $10 billion each year.
New drugs can also be more dangerous. As a result of advice from their staff of specially trained pharmacists, the Kaiser Permanente Health System's Drug Information Services never added the painkiller Vioxx or the MS drug Tysabri to its formulary list of covered prescription drugs. Doctors were allowed to prescribe them only if there was no alternative.
Both Vioxx and Tysabri were eventually pulled from the market; Vioxx because of increased risk of heart attack and stroke, and Tysabri because it could cause a rare neurological disease called progressive multifocal leukoencephalopathy, or PML.