Table 1

Evidence of effects of switching medication products during the treatment of psychiatric illness; based on studies published in 2010-2017 of medications for seizures or bipolar disorder, major depressive disorder, psychosis and attention deficit disorder. Reviewed in Blier, 201812

Study type (number of studies)Findings
Initiation of reference versus generic:Are generic products therapeutically equivalent to their reference counterparts?
Retrospective database analyses (five studies)
  • Lower healthcare resource use for generic products in some studies, for reference in others

  • Greater treatment persistence and adherence for generic product or for reference product in different studies

  • Higher rates of augmentation and dose increase for generic product

  • Similar discontinuation rates for reference and generic products

  • Greater improvement in efficacy outcomes with reference product

Reference to generic substitution:Do switches from reference to generic products affect patient outcomes?
Prospective trials: preswitch versus postswitch (three studies)
  • No change in efficacy outcomes or AEs

  • No postswitch dosage adjustments

Prospective trials: switch versus continue (two studies)
  • Improvement in different efficacy outcomes for continuers versus switchers

  • Decrease in treatment satisfaction with efficacy and tolerability after switch

Retrospective database analyses: preswitch versus postswitch (two studies)
  • No change in healthcare resource use

  • No increase in dose or medication change

  • Poorer clinical outcomes

Retrospective database analyses; switch versus continuation (six studies)
  • No increases in healthcare costs and resource use in most studies, but not all

  • Increase in non-persistence, discontinuations, dose changes or adjunctive treatment with switch

Switching from generic to reference: Does any switch affect patient outcomes?
Clinical case series: preswitch versus postswitch (one study)
  • Improvement in efficacy scores with switch to reference product

Retrospective database analyses: switch to reference versus switch to generic (one study)
  • Persistence rates higher for a switch from generic to reference versus from reference to generic