What are some of the rules?

To be sure certain drugs are prescribed and used correctly and only when truly necessary, plans may have certain standard rules, including:

• Prior authorization—This means before the plan will cover these prescriptions, your doctor must contact the
  plan. Your doctor must show that the drug is medically necessary for it to be covered.
  
• Quantity limits—This means how many pills you can get at a time.
• Step therapy—This means one or more similar lower cost drugs must be tried before the step-therapy drug
  is covered (see example below).

Example of step therapy for a patient who needs a drug for heart failure

• Step 1—Dr. Smith wants to prescribe an ACE inhibitor to treat Mr. Mason’s heart failure. There is more than one
  type of ACE inhibitor. Some of the drugs he considers prescribing are brand-name drugs in Mr. Mason’s
  Medicare drug plan. The plan rules require Dr. Smith to prescribe the generic drug lisinopril first. For most people
  generic lisinopril works as well as brand-name drugs.
  
• Step 2—If Mr. Mason takes lisinopril but has side effects or limited improvement, his doctor can prescribe a
  brand-name drug, like Prinivil® or Zestril®. Mr. Mason’s Medicare drug plan will now cover this drug.