Off-label prescribing, the practice of prescribing drugs for a purpose that the drug has not been approved for, may be commonplace and legal, but researchers say that in many cases there is simply not enough evidence to justify prescribing drugs off-label.
Randall Stafford, MD, PhD, associate professor of medicine at the Stanford Prevention Research Center, and colleagues have drawn up a list of 14 commonly prescribed medications for which there is an urgent need of additional study to determine how effective and safe they are for their off-label uses.
Number one on the list is the drug quetiapine (Seroquel®), an antipsychotic drug approved for the treatment of schizophrenia. Results of the study showed that 76% of all uses of quetiapine are off-label, however its high cost at $207 per prescription, heavy marketing, and the fact that it has a black-box warning from the FDA, all raised serious concerns with the researchers. The other drugs in the list are: warfarin, escitalopram, risperidone, montelukast, bupropion, sertraline, venlafaxine, celecoxib, lisinopril, duloxetine, trazodone, olanzapine, and epoetin alfa.
“Off-label prescribing means that we’re venturing into uncharted territory where we lack the usual level of evidence presented to the FDA that tells us these drugs are safe and effective,” said Professor Stafford in a news release. “Many patients and physicians assume that the FDA has scrutinized all of the different ways a drug can be used, but they’ve only examined those uses that have gone through the approval process.”
The authors concluded: “Future research into off-label drug use should focus on drugs used frequently with inadequate supporting evidence, particularly if further concerns are raised by known safety issues, high drug cost, recent market entry, and extensive marketing. Our quantitative analysis identified particular concerns with the off-label use of antipsychotic and antidepressant drugs.”
Walton SW, Schumock GT, Lee KV, Alexande GC, Meltzer D, Staffrd RS.Prioritizing Future Research on Off-Label Prescribing: Results of a Quantitative Evaluation. Pharmacotherapy. 2008;28:1443-1452. doi: 10.1592/phco.28.12.1443
News release: 14 drugs identified as most urgently needing study for off-label use, Stanford professor says. Stanford University Medical Center. November 24th 2008.