Medicare Prescription Drug Plan By law, Medicare prescription drug plans must cover certain drugs, but are prohibited from covering many others. Drugs prescribed for off-label uses are likely to be denied unless its use is listed in one of three Medicare approved drug compendia. Requests for an exception (appeal) to a Medicare Prescription drug plan should be made under the following circumstances: The medically necessary drug, preferred route of administration or dose is not on the plan’s formulary The prescriber believes a generic substitution will be ineffective or cause harm The plan requires step therapy or limits the prescribed quantity The prescribed drug is in a higher “tier” than similar drugs on the formulary By law, Medicare prescription drug plans must cover certain drugs, but are prohibited from covering many others. Drugs prescribed for off-label uses are likely to be denied unless its use is listed in one of three Medicare approved drug compendia. Requests for an exception (appeal) to a Medicare Prescription drug plan should be made under the following circumstances: The medically necessary drug, preferred route of administration or dose is not on the plan’s formulary The prescriber believes a generic substitution will be ineffective or cause harm The plan requires step therapy or limits the prescribed quantity The prescribed drug is in a higher “tier” than similar drugs on the formulary