The introduction of three-tiered copayment systems represents a significant shift in how cost-sharing is applied to pharmaceutical benefits. Alongside a general increase in the level of cost-sharing required, these systems give a higher level of choice to the consumer in making pharmacotherapy decisions. Whereas in the past, the only difference in cost-sharing was between generic and branded products, three-tiered systems allow consumers a choice between two types of branded products: preferred and non-preferred. Consumers will be reimbursed for non-preferred products, but the cost-sharing required to obtain these products is significantly higher than for preferred products. Therefore consumers are allowed to make a value tradeoff on their own: is the difference in preference, efficacy, or side effects worth the difference in cost.
Although three-tiered copayment plans currently proposed cut across all drug classes, it is reasonable to assume that these plans will have a more significant impact on any group of patients who have one or more chronic, debilitating illness, such as a mental illness. This is because patients may be required to incur the higher levels of cost-sharing for one or more maintenance medication in addition to the cost sharing incurred for prescriptions to treat acute conditions.