When a doctor prescribes a drug for a use not approved by the Food and Drug Administration—“off-label” prescribing—the patient can be at risk for serious side effects, a new study finds.
In a review of off-label prescribing, a Canadian-U.S. research team found that patients who were prescribed drugs off-label without strong scientific evidence were 54 percent more likely to experience an adverse event such as a drug reaction, drug interaction or allergic response that forces them to stop taking the drugs, HealthDay reports.
Off-label prescribing in not against the law. A physician may legally prescribe any FDA-approved drug for any use he or she deems appropriate for the patient, and doctors are not required to document the reason for prescribing a particular drug, according to HealthDay. Doctors have many reasons for off-label prescribing. The medications available to treat a condition may be limited and the patient may have exhausted the drug options. Medicines with good evidence of safety and effectiveness may not have gone through the FDA approval process. Dr. Randall Stafford, director of the Program on Prevention Outcomes and Practices at Stanford University, said, “Off-label use is higher than it should be, in part because the FDA does less than physicians and the public thinks it does.” Stafford said the FDA judges a drug’s safety and effectiveness for a single clinical condition, while many physicians think of FDA approval as “a blanket endorsement.” This can lead to drugs being used for clinical conditions for which they have not been evaluated.
For this study, the researchers examined electronic health record data for about 46,000 adult patients in Quebec who received more than 151,000 prescriptions from primary care clinics from 2005 through 2009. In that record system, physicians must enter the reason for a new prescription, a change in dosage, or discontinuation of a medicine, HealthDay explains. The record must also include any adverse drug events. According to the study, more than one in 10 prescriptions were for an off-label use, and more than 80 percent were for uses lacking strong scientific evidence, the researchers said. The study was published online in JAMA Internal Medicine.
The study authors identified 3,484 adverse drug events, though they acknowledged that the study might not have captured all medication-related events, according to HealthDay. Doctors can miss symptoms or patients may not mention all of their symptoms to the doctor. The authors estimated average cost per adverse event ranges from $759 to $1,214, including possible emergency room visits and hospitalizations.
Among drugs commonly prescribed off-label, the research team found that the antidepressant Oleptro (trazodone), often prescribed for insomnia, was linked to hallucinations. Weight gain was associated with the schizophrenia drug Zyprexa (olanzapine), which is often prescribed off-label for depression, HealthDay reports. The powerful antipsychotic drugs—Seroquel (quetiapine), Risperdal (risperidone), and Zyprexa—are prescribed off-label despite the lack of strong scientific evidence for those uses.
Dr. Tewodros Eguale, the lead researcher of a team at McGill University said, “We are not saying that off-label is bad.” But when there is no strong scientific evidence for a particular use, he said, the study “showed that there’s a high risk of adverse drug events.”