title: Copayment coupons undermine formularies.
mesh_terms: D017047:Cost Sharing; D016527:Drug Costs / Q000639:trends; D004345:Drug Industry / Q000191:economics*; D016568:Drugs, Generic / Q000191:economics*; D005569:Formularies as Topic; D006801:Humans; D009042:Motivation; D055553:Prescription Drugs / Q000191:economics*; D011306:Prescription Fees / Q000639:trends
chemical_list: D016568:Drugs, Generic; D055553:Prescription Drugs