Retirees, Beware: Medicare Won’t Pay for These Drugs in 2026

Medicare Part D coverage is never static, but 2026 is shaping up to be a particularly volatile year for formularies.

Thanks to new legislation and aggressive cost-cutting by plan administrators, several high-profile medications are moving to the excluded list. If you rely on these prescriptions, you could face hefty prices at the pharmacy in 2026 instead of your usual copay.

The biggest driver of this shift is competition. Plans are swapping expensive brand-name drugs for cheaper alternatives, while federal law continues to block coverage for other categories entirely.

Here’s a look at medications that Medicare won’t cover.

Biosimilar swaps

The most significant change for 2026 involves biologic drugs used to treat autoimmune conditions like rheumatoid arthritis and Crohn’s disease.

For years, Humira (adalimumab) was the world’s best-selling drug. However, major pharmacy benefit managers are aggressively dropping brand-name Humira from their covered lists.

They are replacing it with biosimilars, which are drugs that are clinically equivalent but significantly cheaper. If you take Humira, expect your plan to push you toward alternatives like Cyltezo, Hyrimoz or Amjevita.

This isn’t necessarily bad news as biosimilars work the same way, but it does mean you can’t auto-renew your current prescription without checking your plan first.

Lifestyle exclusions

Beyond the formulary swaps, Medicare Part D is legally prohibited from covering certain classes of drugs, often categorized as lifestyle medications. While this isn’t new law, many enrollees are caught off guard when they realize their plan won’t pay a dime for them.

These are the most common exclusions you will see in 2026:

• Weight-loss drugs: The big headlines belong to GLP-1 agonists like Wegovy and Zepbound. If prescribed strictly for weight loss, Medicare cannot cover them. (Note that coverage for Ozempic is possible if prescribed for treating Type 2 diabetes, and Wegovy may be covered if it’s used to reduce heart disease risk.)
• Erectile dysfunction (ED) medications: Brand names like Viagra and Cialis are statutorily excluded.
• Hair growth treatments: Medications for cosmetic hair growth, such as Propecia (finasteride) and prescription minoxidil, are not covered.
• Cosmetic agents: Drugs used primarily for cosmetic purposes, such as Renova (for wrinkles), are out.

Other surprising exclusions

The exclusion list doesn’t stop at lifestyle drugs. You typically will not find coverage for:

• Prescription vitamins and minerals.
• Cough and cold relief: Most prescription syrups and decongestants.
• Desensitizing agents: Drugs used to treat tooth sensitivity (such as prescription toothpastes).

Steps to take

If your medication is on the chopping block, don’t panic. You have options, but you need to move quickly.

1. Read the Annual Notice of Change. Every fall, you receive an Annual Notice of Change (ANOC) letter. Do not throw this away. It explicitly lists changes to your plan’s formulary. If your drug is moving to a higher tier or being dropped, this document will tell you.
2. Request a tiering exception. If your plan drops a drug you need or moves it to an expensive tier, your doctor can file for a formulary exception. You must prove the covered alternative (like a biosimilar) wouldn’t work as well for you. It’s paperwork-heavy, but often successful.
3. Shop the competition. If your current plan drops your drug, fire them. Use the Medicare Plan Finder tool during open enrollment (Oct. 15 through Dec. 7). Enter your specific drugs, and the tool will show you which plans still cover them.

Your health needs might not change in 2026, but your insurance coverage almost certainly will. Check your formulary now so you aren’t left facing an unexpected bill at the pharmacy.