Medicare Coverage for Crohn's and Ulcerative Colitis: Biologics, Infusions, and Costs

Does Medicare Cover Crohn’s Disease and Ulcerative Colitis?

Yes. Medicare covers inflammatory bowel disease comprehensively across all three parts - diagnosis, biologics, surgery, and long-term monitoring.

Covered under Medicare:

• Gastroenterologist visits and specialist consultations (Part B, 20% coinsurance)
• Diagnostic and surveillance colonoscopies, CT/MR enterography, biopsies (Part B, 20%)
• Lab tests: CBC, CRP, fecal calprotectin, therapeutic drug monitoring (Part B, no coinsurance)
• Infused biologics - infliximab (Remicade), vedolizumab (Entyvio), ustekinumab IV induction (Part B, 20% - no annual cap)
• Self-injected biologics - adalimumab (Humira), risankizumab (Skyrizi), certolizumab (Cimzia) (Part D, capped at $2,100/year)
• Oral JAK inhibitors - tofacitinib (Xeljanz), upadacitinib (Rinvoq) (Part D, capped at $2,100/year)
• Conventional drugs: mesalamine, azathioprine, 6-mercaptopurine, methotrexate (Part D, inexpensive generics)
• Corticosteroids for flares: prednisone, budesonide (Part D, inexpensive)
• Inpatient hospitalizations for severe flares or surgery (Part A)
• Bowel resection, colectomy, ileostomy surgery (Part A/B)
• Ostomy supplies as durable medical equipment (Part B, 20%)

Not covered or with significant gaps:

• Medigap/supplement premiums (separate private policy - but highly recommended to eliminate uncapped Part B infusion coinsurance)
• Nutritional supplements and enteral formula for home use (limited Medicare coverage)
• Infused biologic coinsurance has no annual ceiling under Original Medicare alone

2026 IBD Cost Snapshot (Original Medicare without supplement):

The most important financial decision for an IBD patient on Medicare is whether your biologic is infused or self-injected - and securing Medigap Plan G during your open enrollment window at 65 to eliminate the uncapped Part B infusion exposure.

Inflammatory bowel disease (IBD)—Crohn’s disease and ulcerative colitis—is a lifelong autoimmune condition, and while it’s often diagnosed in young adulthood, a large and growing share of patients are over 65 and managing it on Medicare. The modern treatment of IBD revolves around biologic drugs, which are extraordinarily effective and extraordinarily expensive. How Medicare pays for those biologics—and how much you owe—depends on one technical detail that catches many beneficiaries off guard: whether the drug is infused or self-injected. This guide walks through the entire path, from diagnosis to surgery, with a sharp focus on the drug-cost split that drives your out-of-pocket exposure.

Diagnosis and Monitoring Under Part B

The workup and ongoing monitoring of IBD are covered under Part B at 80 percent after the $283 deductible (2026), leaving you 20 percent coinsurance:

• Gastroenterologist visits — 20 percent coinsurance
• Colonoscopy and upper endoscopy with biopsy — when performed to diagnose or monitor disease (a diagnostic colonoscopy), 20 percent coinsurance applies. Note: a screening colonoscopy for colorectal cancer is free, and because IBD counts as high-risk, Medicare covers screening colonoscopies as often as every 24 months at no cost — but scopes ordered to assess active disease are diagnostic and carry cost-sharing. (If a screening colonoscopy turns therapeutic with a polyp removal, the coinsurance is reduced — 15 percent in 2026, phasing to zero by 2030.) Our Medicare colonoscopy screening guide explains the screening-vs-diagnostic billing lanes in detail.
• CT and MR enterography to image the small bowel — 20 percent coinsurance
• Lab monitoring — blood counts, inflammatory markers (CRP), and fecal calprotectin are covered as clinical laboratory tests, generally at no coinsurance
• Therapeutic drug monitoring — measuring biologic drug levels and antibodies to guide dosing — covered under Part B

Because IBD requires lifelong surveillance—including regular colonoscopies due to the elevated colorectal cancer risk in long-standing colitis—these costs recur for life.

The Heart of IBD Cost: Infused vs. Self-Injected Biologics

Modern IBD is treated with biologics and targeted small molecules, and this is where Medicare’s coverage rules create dramatically different bills for what is medically similar treatment. The governing principle is the same one that runs throughout Medicare: how a drug is administered determines which part of Medicare pays. For the underlying framework, see Part B vs. Part D drugs.

Infused biologics → Part B (20%, no annual cap)

Biologics given by intravenous infusion in a clinic or hospital outpatient department fall under Part B, at 20 percent coinsurance with no annual out-of-pocket limit:

• Infliximab (Remicade, and biosimilars Inflectra, Avsola, Renflexis) — IV every 8 weeks
• Vedolizumab (Entyvio) — IV induction and maintenance
• Ustekinumab (Stelara) — the IV induction dose is given as a Part B infusion

A maintenance infliximab infusion can carry a cost in the range of $3,000–$6,000+ per session depending on dose and biosimilar, so 20 percent coinsurance is roughly $600–$1,200 every eight weeks—potentially $4,000–$8,000 a year, every year, with no cap under Original Medicare without a supplement.

Self-injected and oral drugs → Part D (capped at $2,100)

Drugs you inject yourself at home or take by mouth fall under Part D, where your total out-of-pocket is capped at $2,100 for the year (2026):

• Adalimumab (Humira, and biosimilars) — self-injected pen
• Ustekinumab (Stelara) maintenance — self-injected (after the IV induction dose)
• Risankizumab (Skyrizi), certolizumab (Cimzia), golimumab (Simponi) self-injected — Part D
• Oral targeted small molecules — tofacitinib (Xeljanz) and upadacitinib (Rinvoq) JAK inhibitors, and ozanimod (Zeposia) — all Part D
• Conventional maintenance drugs — mesalamine (Asacol, Lialda, Apriso), azathioprine, 6-mercaptopurine, methotrexate pills — inexpensive Part D generics

See Medicare Part D explained for how the $2,100 cap works.

The counterintuitive result

A patient on self-injected Humira or Skyrizi pays at most $2,100 for the entire year. A patient on infused Remicade or Entyvio can pay much more, because Part B has no cap. The drugs treat the same disease with similar effectiveness—but the route of administration, not the medicine, determines your bill. This is the most important financial fact in IBD coverage, and it means the choice between an infused and a self-injected biologic has real out-of-pocket consequences for someone on Original Medicare without a supplement.

This also means it’s worth discussing administration route with your gastroenterologist as a financial matter—where two options are clinically reasonable, a self-injected biologic under Part D may cost you far less than an infused one under Part B.

Why Medigap Plan G Erases the Infusion Exposure

Because infused biologics under Part B carry 20 percent coinsurance with no annual cap, the most important financial protection for an IBD patient on Original Medicare is a Medigap (Medicare Supplement) policy.

Plan G pays essentially all of the 20 percent Part B coinsurance after the small annual Part B deductible. For a patient on lifelong Remicade or Entyvio infusions, Plan G converts an open-ended $4,000–$8,000+ per year into a predictable monthly premium. See Medigap plans compared and the supplement vs. Advantage cost comparison.

As always, the catch is timing: Medigap is guaranteed-issue without medical underwriting only during your six-month open enrollment window at 65 (and certain special situations). An IBD diagnosis already on your record can make a later Medigap policy expensive or unavailable in most states—so this protection is best secured before you need it.

Medicare Advantage: Caps, but with Catches

A Medicare Advantage plan caps your in-network out-of-pocket each year (2026 maximum $9,250 in-network), which limits the uncapped Part B infusion exposure you’d face under Original Medicare without a supplement. But IBD care exposes the trade-offs sharply:

• Prior authorization and step therapy — MA plans frequently require you to “fail” a cheaper drug before approving an expensive biologic, and may require prior authorization for each infusion
• Networks — your gastroenterologist or specialized IBD center may be out of network
• You still pay toward the out-of-pocket maximum every year

For patients on stable, expensive biologic regimens who value provider choice and the fewest treatment delays, Original Medicare plus Plan G is often preferable—provided Medigap was secured in time.

Flares, Steroids, and Surgery

Acute flares are managed with corticosteroids (prednisone, budesonide—inexpensive Part D drugs) and sometimes hospitalization. A severe flare requiring inpatient admission falls under Part A and its $1,736 (2026) deductible per benefit period, governed by the two-midnight rule.

When medication fails, surgery may be needed—bowel resection for Crohn’s, or colectomy with ileostomy or J-pouch for ulcerative colitis. Inpatient surgery falls under Part A, with surgeon fees under Part B at 20 percent coinsurance. Ostomy supplies are covered under Part B as durable medical equipment / prosthetic supplies at 20 percent coinsurance, and these are an ongoing, lifelong cost for patients with a permanent stoma.

Help for Lower-Income Beneficiaries

If your income and assets are limited:

• Medicare Savings Programs can pay your Part B premium and, at the QMB level, your Part B coinsurance—erasing the 20 percent exposure on infused biologics. See Medicare Savings Programs.
• Extra Help (Part D Low-Income Subsidy) brings self-injected biologic copays down to a few dollars.
• Manufacturer patient assistance programs exist for most biologics, though some have restrictions for patients with Medicare drug coverage—a foundation grant is often the route for Medicare patients.

The Bottom Line

Medicare covers IBD comprehensively—diagnosis, monitoring, biologics, flares, and surgery—but your out-of-pocket cost hinges on how your biologic is delivered:

• 20% with no cap — infused biologics (Remicade, Entyvio, Stelara IV induction) and other Part B services (the largest exposure)
• Capped at $2,100/year — self-injected biologics (Humira, Skyrizi, Cimzia), oral JAK inhibitors, and conventional pills under Part D

The most important protective step is securing Medigap Plan G during your open enrollment window, before diagnosis—because it’s the uncapped Part B infusion coinsurance, not the Part D drugs, that creates the runaway bills. For how these recurring costs fit into a lifetime plan, see healthcare costs in retirement.

Frequently Asked Questions

Does Medicare Part D cover Humira (adalimumab) for Crohn’s disease or ulcerative colitis?

Yes. Adalimumab (Humira) and its biosimilars are self-injected at home, which places them under Part D. Under the redesigned 2026 Part D benefit, your total out-of-pocket spending on all covered drugs is capped at $2,100 for the year. Most people on Humira hit the $2,100 cap within the first one to two months and then pay $0 for the rest of the year. Confirm your specific plan’s formulary during open enrollment, since covered biologics can change year to year.

How much does infliximab (Remicade) cost on Medicare?

Infliximab infusions are billed under Part B at 20 percent coinsurance with no annual cap. A single maintenance infusion typically runs $3,000-$6,000 depending on dose and whether a biosimilar is used; 20 percent coinsurance is roughly $600-$1,200 per infusion. With infusions every eight weeks (about six to seven per year), a patient on Original Medicare without a supplement can owe $4,000-$8,000 per year or more in Part B coinsurance alone - indefinitely. Medigap Plan G eliminates this exposure after a small annual deductible ($283 in 2026). This cost difference between infused (Part B, no cap) and self-injected (Part D, $2,100 cap) is the most important financial fact in IBD Medicare coverage.

Can I get Medicare before age 65 if I have Crohn’s disease or ulcerative colitis?

Possibly. IBD itself does not automatically qualify you for Medicare before 65, but Medicare opens early if your IBD is severe enough to meet the Social Security Administration’s disability standard and you have been receiving Social Security Disability Insurance (SSDI) benefits for 24 consecutive months. Crohn’s disease and ulcerative colitis can qualify for SSDI if the condition causes significant functional limitations despite treatment - including repeated hospitalizations, malnutrition, fistulas, or failure of multiple medication regimens. The 24-month SSDI waiting period runs before Medicare eligibility begins, so the total wait from approval to Medicare is typically two years.

What is the difference between Part B and Part D coverage for IBD biologics?

The key difference is how the drug is administered:

• Infused biologics (IV in a clinic) - covered under Part B at 20 percent coinsurance with no annual out-of-pocket limit. Drugs in this group: infliximab (Remicade/Inflectra/Avsola), vedolizumab (Entyvio), ustekinumab IV induction (Stelara).
• Self-injected or oral drugs (at home) - covered under Part D, capped at $2,100 per year (2026). Drugs in this group: adalimumab (Humira), risankizumab (Skyrizi), ustekinumab maintenance SC (Stelara), certolizumab (Cimzia), tofacitinib (Xeljanz), upadacitinib (Rinvoq), and all conventional pills. The same drug can sometimes be given both ways (ustekinumab, for example, starts with an IV induction dose under Part B and then switches to self-injected maintenance under Part D). The administration route - not the drug name - drives which part pays.

Does Medicare Advantage cover biologic infusions for IBD?

Yes, but with important trade-offs. Medicare Advantage (Part C) plans cover the same IBD services as Original Medicare, but they frequently add prior authorization requirements before approving expensive biologics, and may require step therapy - meaning you must try (and fail) a preferred drug before they will approve a more expensive one. Networks can also be a limiting factor if your IBD specialist or infusion center is out of network. On the other hand, MA plans cap your annual out-of-pocket (maximum $9,250 in-network in 2026), which protects against the uncapped Part B infusion coinsurance that makes Original Medicare without a Medigap supplement risky for IBD patients. For stable patients on expensive infusions who value provider choice and minimal treatment delays, Original Medicare plus Medigap Plan G is often the better structure.

Does Medicare cover ostomy supplies after colectomy or bowel resection?

Yes. Ostomy supplies - pouches, skin barriers, irrigation sets, and accessories - are covered under Part B as durable medical equipment (DME) at 20 percent coinsurance after the Part B deductible. Because these are an ongoing, lifelong cost for patients with a permanent ostomy (ileostomy or colostomy), Medigap Plan G, which covers this 20 percent coinsurance, effectively makes ostomy supplies cost-free after the small annual deductible. A Medicare-enrolled ostomy supply company will bill Part B directly; you should not need to pay upfront and seek reimbursement.

Sources

• Medicare.gov — Colonoscopy coverage
• Medicare.gov — Drug coverage (Part D)
• Medicare.gov — Medicare costs
• CMS.gov — 2026 Medicare Parts A & B premiums and deductibles (fact sheet)

All sources are official government or nonprofit consumer resources, verified July 2026. Medicare and Social Security rules and dollar amounts change annually — confirm current figures at the links above before making decisions.