A Medicare Part D formulary is the list of prescription drugs covered by a Medicare drug plan. Every standalone Part D plan and Medicare Advantage plan with drug coverage has its own formulary.
This list matters because Medicare drug plans do not all cover medications in the same way. A medicine that is covered by one plan may not be covered by another plan. Even when two plans cover the same drug, they may place it in different cost levels, called tiers.
Before choosing a Medicare drug plan, it is usually wise to check the plan’s formulary for every prescription you take. This can help you understand whether the plan fits your medications and pharmacy preferences.
What does a Part D formulary include?
A formulary is more than a simple list of drug names. It may show whether a medication is covered, which tier it is on, and whether the plan has rules you must meet before it will cover the drug.
Part D plans generally must cover a broad range of prescription drugs. They also must cover medications in certain protected drug classes, such as many drugs used for cancer, HIV, seizures, and organ transplants. Still, plans can have different formularies and coverage rules.
Most formularies include both brand-name drugs and generic drugs. A generic drug has the same active ingredient as its brand-name version, but it may cost less in many situations. Your doctor or pharmacist may be able to tell you whether a generic option is available for a medication you use.
How do Medicare drug tiers work?
Part D plans group covered medications into tiers. A tier is a cost level. In general, drugs on lower tiers tend to have lower out-of-pocket costs than drugs on higher tiers, though actual costs vary by plan, pharmacy, and state.
- Tier 1: Often preferred generic drugs.
- Tier 2: Often other generic drugs.
- Tier 3: Often preferred brand-name drugs.
- Tier 4: Often non-preferred drugs, including some brand-name medications.
- Specialty tier: Often used for higher-cost drugs that may treat complex conditions.
Not every plan uses the exact same number of tiers or the same tier names. One plan might place a medication on a preferred brand tier, while another plan might put the same medication on a higher tier. That difference may affect what you pay at the pharmacy.
Why might a covered drug still have restrictions?
Seeing a medication on a formulary is an important first step, but you should also look for coverage restrictions. A plan may cover a drug only after certain requirements are met.
- Prior authorization: Your doctor may need to provide information showing why you need the medication before the plan covers it.
- Step therapy: The plan may ask you to try another covered medication first, often a lower-cost option, before it covers the prescribed drug.
- Quantity limits: The plan may limit how much medication it covers during a certain period, such as 30 days.
These rules do not always mean you cannot get your medication. Your doctor may be able to request an exception when medically appropriate. The plan must review the request, but approval is not guaranteed.
What if my prescription is not on the formulary?
If a drug is not covered, do not assume you have no options. First, check whether there is a similar covered drug your doctor believes may work for you. You can also ask your plan for a formulary exception.
An exception is a request for the plan to cover a drug that is not normally covered or to cover it at a lower cost tier. Your prescribing doctor generally needs to support the request by explaining why a covered alternative may not be appropriate for you.
If your request is denied, you may have appeal rights. The plan’s denial notice should explain the next steps and deadlines. It can be helpful to save copies of notices, prescriptions, and information from your doctor.
Can a Medicare Part D formulary change during the year?
Yes. Drug plans may make changes to their formularies during the year in certain situations. For example, a plan may add a new generic medication, change a drug’s tier, or remove a drug when a similar medication becomes available.
Plans generally must provide notice when a change affects a medication you are taking. The notice may explain whether you have time to refill your prescription under the old rules or whether the plan will offer a temporary supply while you discuss options with your doctor.
Because plan rules can change, it is a good habit to read mail from your drug plan. A notice may look routine, but it could affect a medication you rely on.
Why should you review your medications every year?
Medicare Part D plans can change their premiums, pharmacy networks, formularies, and drug tiers from one year to the next. Your own prescriptions may also change. A plan that worked well last year may not be the best fit for the coming year.
During Medicare’s Annual Enrollment Period, which generally runs from October 15 through December 7, you can review your drug coverage for the following year. Entering your exact medications, dosage, and preferred pharmacy into Medicare’s plan comparison tools can give you a more complete picture.
It is important to enter the medication details carefully. A small difference in dosage, tablet strength, or whether you take a drug once or twice daily can affect the results.
How does a formulary fit into your overall Medicare choice?
Your drug coverage is one part of your Medicare decision. If you choose Original Medicare, you can pair it with a standalone Part D plan and may also consider a Medicare Supplement plan to help with certain gaps in Original Medicare. Medicare Supplement plans do not include outpatient prescription drug coverage, so a separate Part D plan is generally needed if you want that coverage.
Medicare Advantage plans often include prescription drug coverage, but you should still review the plan’s formulary, provider network, and other plan rules. The right choice often depends on your medications, doctors, budget, and comfort with the plan’s structure.
Understanding a formulary may feel like one more Medicare task, but it can help you avoid surprises at the pharmacy. If you would like free, no-pressure help reviewing Medicare drug coverage or how it may work alongside a Medicare Supplement plan, reach out to Eric for guidance based on your needs.