This is a list of all the prescription drugs the plan covers.įormularies often include at least two medications for each drug class. Original Medicare is made up of Part A (hospital insurance) and Part B (medical insurance).Ĭompanies that sell Part D plans will have a formulary. Part D plans are sold by private insurance companies and can be added to your original Medicare coverage. It’s usually covered through Medicare Part D, which is Medicare’s prescription drug coverage. Medicare does provide coverage for Humira.