Prescribing antidepressants for off-label indications in primary care is often not supported by strong evidence for the respective indication, according to data published in the BMJ.
Jenna Wong, MSc, from the Department of Epidemiology, Biostatistics, and Occupational Health at McGill University in Montreal, and colleagues examined off-label indications in primary care to determine the level of scientific support for off-label prescribing. The researchers studied antidepressant prescriptions written by primary care clinicians using an indication based on an electronic prescribing system.
The study included primary care practices near 2 major urban centers in Quebec, Canada. Participants were older than 18 years of age, visited a study physician between January 2003 and September 2015, and were prescribed an antidepressant through the electronic prescribing system. The main outcome was the prevalence of off-label indications for antidepressant prescriptions by class and by individual drug.
A total of 106,850 prescriptions for antidepressants were written by 174 physicians for 20,920 adults. Tricyclic antidepressants had the highest prevalence of off-label indications (81.4%) due to a high off-label prescribing rate for amitriptyline (93%). Trazodone use for insomnia was the most common off-label use for antidepressants and accounted for 26.6% of all off-label prescriptions.
The investigators found that for 15.9% of all off-label prescriptions, the prescribed drug had strong scientific evidence for the respective indication. In addition, 39.6% of off-label prescriptions did not have strong evidence for the prescribed drug, but another antidepressant in the same class had strong evidence for the respective indication. For the remaining 44.6% of off-label prescriptions, the prescribed drug and the other drugs in the class did not have strong evidence for the indication.
“These findings highlight an urgent need to produce more evidence on the risks and benefits of off-label antidepressant use and to provide physicians with this evidence at the point of prescribing,” the authors concluded.
“Technologies such as indication based e-prescribing systems and electronic health records have the potential to become essential components of effective post-market drug surveillance systems for monitoring and evaluating off-label antidepressant use. By integrating these technologies with knowledge databases and clinical decision support tools, they could also provide an effective means for communicating evidence back to physicians to optimize prescribing decisions.”
- Wong J, Motulsky Am Abrahamowicz M, Eguale T, Buckeridge DL, Tamblyn R. Off-label indications for antidepressants in primary care: descriptive study of prescriptions from an indication based electronic prescribing system. BMJ. 2017. doi:10.1136/bmj.j603