Formulary Restriction of Selective Serotonin Reuptake Inhibitors for Depression: Potential Pitfalls
Authors: Hensley PL, Nurnberg HG.
Psychotropic drugs and their associated costs can be a limiting factor in mental health treatment coverage. For this reason, restrictive formularies are a common method of attempting to limit costs.This paper explores the intended and unintended consequences of having a single or exclusive selective serotonin reuptake inhibitor (SSRI) on a formulary. Central to this discussion is an assumption of the interchangeability of SSRIs, so the authors examined the evidence for and against this through a model to determine the probability of interchangeability. The authors conclude that the practice of having a single SSRI on the formulary for a health care plan seems ill founded. Patients who switch antidepressants remain in treatment 50% longer and cost approximately 50% more to treat in a more costly treatment setting. Giving the primary care physician several antidepressant choices can provide more options to continue treatment of his or her patient in the less expensive primary care setting. In terms of cost containment, formulary restrictions are far more likely to have the opposite effect.