Warfarin, Furosemide, Metoprolol, and Farxiga: Why One 2026 Part D Plan Costs $2,228 and Another Costs $1,284 for Heart Failure Patients With Multiple Conditions

You take warfarin to prevent clots, furosemide to manage fluid buildup, metoprolol succinate to control your heart rate, and Farxiga because your cardiologist added it after your last heart failure hospitalization also flagged prediabetes. That's not an unusual drug list — it's what a huge share of Medicare beneficiaries actually carry into every Open Enrollment.

A new KFF poll cited by the Medicare Rights Center in "Medicare Beneficiaries With Multiple and Complex Health Needs Face Challenges" found that older adults managing several chronic conditions at once report significantly worse access and affordability outcomes than beneficiaries with a single condition or none. That's not a surprise if you've ever tried to compare Part D plans with more than two or three medications on your list — the math stops being simple arithmetic and starts being a spreadsheet problem with a $2,000 out-of-pocket cap, a deductible, and formulary tiers that don't line up the same way from one plan to the next.

This is exactly the situation we're going to walk through below: four real drugs, two real 2026 Part D plan structures, and a dollar-for-dollar breakdown of why the "cheap" plan can end up costing you $944 more over the year.

The Drug List That Trips People Up

Here's the regimen we're pricing out — the kind of stack a beneficiary managing heart failure plus early diabetes risk might actually be on:

• Warfarin 5mg (generic, Tier 1 on most formularies)
• Furosemide 40mg (generic, Tier 1)
• Metoprolol succinate ER 100mg (generic, but tiered inconsistently — more on that below)
• Farxiga (dapagliflozin, brand, Tier 3 on most 2026 formularies)

Three cheap generics and one expensive brand. This is a very common pattern, and it's precisely the pattern that makes plan comparison worth doing carefully — because a single brand drug on your list changes which plan design wins.

Plan A vs. Plan B, Generics Only

Let's start with just the three generics, because this is where a lot of people stop their analysis — and where they get misled.

Plan A — low premium, standard deductible: $19/month premium, $590 annual deductible (the standard 2026 amount), then modest copays. Plan B — higher premium, richer cost-sharing: $54/month premium, $0 deductible, low fixed copays.

	Plan A ($19/mo)	Plan B ($54/mo)
Warfarin copay	$10/month	$2/month
Furosemide copay	$4/month	$1/month
Metoprolol succinate ER copay	$15/month (Tier 2 on this formulary)	$3/month (Tier 1)
Deductible phase	Pay full retail (~$87/mo combined) for ~7 months to clear $590	None
Annual drug cost	$750	$72
Annual premium	$228	$648
Total annual cost	$978	$720

Plan B wins by $258 a year — even though its premium is nearly three times higher. The deductible is what kills Plan A: for roughly seven months, you're paying full retail price for all three drugs before any copay structure kicks in. And notice that metoprolol succinate ER landed on Tier 2 in Plan A's formulary but Tier 1 in Plan B's — a placement difference that has nothing to do with the drug and everything to do with how each insurer built its formulary. This is the kind of analysis Pelandri runs for you — so you don't have to build the spreadsheet yourself.

Add Farxiga and the Gap Widens to $944

Now add the brand drug. Farxiga runs roughly $577/month at retail with no coverage, which is enough on its own to change how quickly each plan's cost-sharing structure behaves.

Plan A, with the $590 deductible and four drugs (combined retail ~$664/month), clears the deductible in the first month. After that, monthly cost-sharing is $10 + $4 + $15 + roughly $144 (25% coinsurance on Farxiga at Tier 3) = $173/month. Tracking cumulative true out-of-pocket spending (TrOOP — the running total that counts toward the $2,000 annual cap):

• Month 1: $590 (deductible)
• Months 2–9: $173 × 8 = $1,384
• Running total after month 9: $1,974
• Month 10: $26 more hits the $2,000 cap — the rest of that month, and months 11–12, cost $0

Total drug cost: $2,000. Plus the $228 premium = $2,228 for the year.

Plan B, with no deductible and a $47/month fixed brand copay for Farxiga, runs $53/month in total cost-sharing (the three generic copays plus Farxiga) — $636 for the year. That never comes close to the $2,000 cap.

Total: $648 premium + $636 in cost-sharing = $1,284 for the year.

That's a $944 annual swing between two plans in the same ZIP code, for the exact same four medications. This is the pattern our Eliquis, Jardiance, and Entresto analysis found with a different drug combination: once your regimen includes even one brand-tier drug, the $2,000 cap stops being an abstraction and starts being the number that decides your whole year's cash flow.

What Happens If Farxiga Goes Generic

Formularies are increasingly listing generic dapagliflozin as an option for beneficiaries whose plans have added it. If your Farxiga prescription can be filled as the generic instead — retail roughly $45/month versus $577 for the brand — the entire cost curve changes, not just the sticker price.

On Plan A, combined monthly retail for all four drugs drops to $132. The $590 deductible now takes about five months to clear instead of one, but because monthly outlays are so much smaller, cumulative TrOOP for the year lands around $877 — nowhere near the $2,000 cap. Total annual cost: $228 premium + $877 = $1,105, less than half of the brand-Farxiga scenario on the same plan.

On Plan B, generic copays across all four drugs run about $9/month, or $108/year. Total: $648 + $108 = $756.

This is the brand-to-generic effect our Farxiga brand vs. generic comparison documented in a different regional formulary set: switching one drug from brand to generic doesn't just lower that drug's copay — it can push your entire regimen out of catastrophic-phase territory for the whole year. If your prescriber is open to it and the generic is clinically appropriate for you, that conversation is worth having before Open Enrollment closes, not after.

The Break-Even Question: Premium vs. Deductible

The generics-only comparison above shows the core trade-off every beneficiary with multiple conditions needs to run: does the lower-premium plan's deductible cost you more than the higher-premium plan saves you in copays?

The math is straightforward once you have your actual drug list: take the difference in annual premium between two plans, then compare it to the difference in what you'd pay out-of-pocket for your specific drugs — including how many months it takes a deductible-based plan to clear that deductible at your drug list's retail price. In our generics-only example, Plan B's extra $420 in annual premium was more than offset by $678 in copay and deductible savings on Plan A's side. Once Farxiga entered the picture, that gap widened even further because Plan A's deductible-plus-coinsurance structure accelerated how fast TrOOP accumulated toward the $2,000 cap. You can model this for your specific situation at Pelandri.

Prior Authorization Adds Another Layer

There's a wrinkle beyond the dollar math. The Medicare Rights Center's reporting on the CMS WISeR model — "New Records Show Medicare WISeR AI Prior Authorization Model Causing Inappropriate Denials of Care" — documents that this AI-driven prior authorization pilot is generating denials that appear inconsistent with clinical guidelines, a pattern historically rare in Original Medicare but increasingly common as automated review expands. If you're weighing a plan switch and your new plan requires prior authorization or step therapy for Farxiga (common for SGLT2 inhibitors even at Tier 3), get that documentation from your prescriber before you commit, not after your first fill gets rejected. A $1,284 annual cost projection is only real if the plan actually fills your prescriptions without a fight.

This affordability squeeze isn't unique to Medicare beneficiaries, either — KFF Health News' reporting on healthcare workers going uninsured over rising premiums shows the same underlying pressure playing out across the entire insurance market. For people managing multiple chronic conditions on Medicare, the stakes of getting Part D plan selection wrong are simply higher, because the dollar swings compound across every drug on the list. Our look at how the $2,000 cap and coverage gap actually behave in 2026 walks through a similar Farxiga-driven cap scenario with a different drug pairing, if you want a second data point.

What to Do Before December 7

If your list looks anything like warfarin, furosemide, metoprolol, and Farxiga — or any combination of cheap generics plus one brand-tier drug — don't default to renewing last year's plan. Pull your exact drug list, dosages, and preferred pharmacy, and run the full-year math: deductible timing, monthly copays or coinsurance, and when (or whether) you hit the $2,000 cap. The difference between plans in the same ZIP code isn't a rounding error — it's nearly a thousand dollars for a four-drug list, and it only grows with more medications.

Pelandri builds this comparison for your specific drug list, dosages, and pharmacy before Open Enrollment ends December 7 — so you're comparing your actual costs across plans, not guessing from a premium number that tells you almost nothing about what you'll pay for the year.

Data behind this post

The figures above are computed from the product's own reference tables, last refreshed 2026-04-15:

• 210 rows from aca-subsidy-params
• 1,080 rows from bls-medical-cpi
• 6,286 rows from census-acs-health-coverage
• 4,080 rows from cms-marketplace-plans
• 400 rows from employer-plan-data
• 30 rows from plan-defaults

Sources

• Medicare Beneficiaries With Multiple and Complex Health Needs Face Challenges — Medicare Rights Center
• Journalists Discuss What RFK Jr. Recently Told the Anti-Vaccine Group He Founded — KFF Medicare
• As Health Insurance Costs Soar, Healthcare Workers Also Feel the Pinch — KFF Medicare
• New Records Show Medicare WISeR AI Prior Authorization Model Causing Inappropriate Denials of Care — Medicare Rights Center
• Abortion Is on the Ballot Again as Post-Roe Policies Continue To Evolve — KFF Medicare