Ursodiol (Actigall, Urso, and others)

How Medicare covers it

Part D (forms used at home). Part A during a covered inpatient stay. No Part B clinician-administered form in the CMS Part B spending file.

What it treats

Ursodiol is a bile acid (ursodeoxycholic acid). This pinned label — the 300 mg capsule — is indicated for dissolving radiolucent, noncalcified gallbladder stones smaller than 20 mm in patients who would otherwise have gallbladder surgery but face increased surgical risk (systemic disease, advanced age, reaction to general anesthesia) or who refuse surgery, and for preventing gallstone formation in obese patients losing weight rapidly. The package behind this page also includes ursodiol tablet forms (Urso, Urso Forte) whose own labels cover primary biliary cholangitis, a liver disease.

What it is for, in depth

From the pinned label's Indications section (300 mg capsules): ursodiol is for patients with radiolucent, noncalcified gallbladder stones under 20 mm in whom gallbladder removal would be the plan except that surgery carries increased risk because of systemic disease, advanced age, or idiosyncratic reaction to general anesthesia — or who refuse surgery — and for prevention of gallstone formation in obese patients experiencing rapid weight loss. So on the treatment path it is the non-surgical option for a narrow group: small, cholesterol-type stones that can actually dissolve, in people who should not or will not have the operation. Dissolution takes months, is checked by ultrasound, and often does not complete. The wider package behind this page also covers ursodiol 200/400 mg capsules and 250/500 mg tablets; the tablet products (Urso, Urso Forte) carry their own FDA labels for primary biliary cholangitis (PBC), the chronic liver disease named in this package's record, dosed by body weight with food and with liver-test monitoring — those PBC facts come from the package record, not from this pinned capsule label.

How it works

Ursodiol is a naturally occurring bile acid. Taken by mouth, about 90% is absorbed in the small bowel, carried to the liver, joined (conjugated) with glycine or taurine, and secreted into bile, where it concentrates in the gallbladder. By changing the make-up of bile it gradually dissolves cholesterol gallstones — a process that takes months of therapy. The label is plain that complete dissolution does not occur in all patients, and stones can come back within 5 years in up to 50% of patients who do dissolve them.

How it is taken

Oral capsules (this label: 300 mg). For gallstone dissolution the recommended dose is 8–10 mg/kg/day given in 2 or 3 divided doses. Gallbladder ultrasound images are taken at 6-month intervals during the first year to check whether stones are shrinking; if stones appear dissolved, treatment continues and dissolution is confirmed on a repeat ultrasound within 1 to 3 months. If partial dissolution is not seen by 12 months, the likelihood of success is greatly reduced. Safety of use beyond 24 months is not established.

Common side effects

In the gallstone-dissolution trial (ursodiol vs placebo), effects reported at 5% or more included abdominal pain 43.2%, diarrhea 27.1%, nausea 14.2%, headache 18.1%, dyspepsia 16.8%, upper respiratory infection 15.5%, viral infection 19.4%, constipation 9.7%, vomiting 9.7%, sinusitis 11.0%, back pain 7.1%, arthralgia 7.7%, pharyngitis 8.4%, coughing 7.1%, and urinary tract infection 6.5% — most at rates close to placebo. In the gallstone-prevention trial: headache 24.8%, constipation 26.4%, diarrhea 25.2%, nausea 17.4%, vomiting 13.7%, dizziness 16.5%, and hair loss (alopecia) 5.3%.

Serious warnings

This label has no boxed warning. Its key limits are about who it cannot help: ursodiol will not dissolve calcified cholesterol stones, radiopaque stones, or radiolucent bile pigment stones, so patients with those stones are not candidates. Patients with compelling reasons for gallbladder surgery — unremitting acute cholecystitis, cholangitis, biliary obstruction, gallstone pancreatitis, or a biliary-gastrointestinal fistula — are not candidates either, and neither are people allergic to bile acids. The label also notes a breakdown product (lithocholic acid) can cause cholestatic liver injury, which is part of why liver monitoring accompanies the tablet forms used for liver disease.

Who should be careful

People whose gallstones are calcified, radiopaque, or pigment stones (the drug cannot dissolve them); people with acute gallbladder inflammation, bile-duct infection or obstruction, gallstone pancreatitis, or a biliary fistula (they need surgery, not this drug); people allergic to bile acids; people taking bile-acid sequestrants or aluminum antacids (absorption problems); and people on estrogens or clofibrate-type drugs (they work against stone dissolution).

Major interactions

Bile acid sequestering agents such as cholestyramine and colestipol may interfere with ursodiol by reducing its absorption. Aluminum-based antacids adsorb bile acids and may be expected to interfere the same way. Estrogens, oral contraceptives, and clofibrate (and perhaps other lipid-lowering drugs) increase liver cholesterol secretion and encourage cholesterol gallstone formation, so they may counteract the effectiveness of ursodiol.

Cost and saving notes

Ursodiol is a generic medicine listed by essentially all Part D plans in the CMS data behind this page, most often on a mid (preferred brand) tier — see the tier section. If a plan prices the capsule and tablet forms differently, asking the pharmacist which form the plan prefers can lower the copay; a tier exception and Extra Help are the other standard routes.

Why it is in its tier

Ursodiol (Actigall, Urso, and others) sits on Tier 3 in 47.41% of the plans that list it (2605 of 5495 listing plans). Tier 3 is the preferred brand tier — mid-level copays or coinsurance. The data-visible drivers: It is a generic product, and the CMS dashboard puts its average Part D spending at about $696 per beneficiary for 2024 — a relatively low-cost drug, which matches where plans place it. It is listed by 100.0% of Part D plans. The tier shown is the most common one; individual plans vary.

Sources

• URSODIOL CAPSULE [ACTAVIS PHARMA, INC.] — DailyMed
• MedlinePlus — Ursodiol

What official patient guides say

Ursodiol comes as a capsule to take by mouth (the form in this package). To treat gallstones it is usually taken two or three times a day, with or without food. Take it exactly as directed — do not take more, less, or take it more often than prescribed by your doctor. This medication must be taken for months to have an effect. If you are taking ursodiol capsules to dissolve gallstones, you may need to take it for up to 2 years. Your gallstones may not completely dissolve, and even if they do dissolve, gallstones may come back within 5 years after successful treatment. Continue to take ursodiol even if you feel well, and do not stop taking it without talking to your doctor. If you miss a dose, take it as soon as you remember. If it is almost time for the next dose, skip the missed dose and go back to your regular schedule. Do not take a double dose. Keep it in the container it came in, tightly closed and out of reach of children. Store it at room temperature, away from extra heat and moisture, and not in the bathroom.

Source: MedlinePlus — Ursodiol

Part D formulary coverage

Source: CMS Prescription Drug Plan Formulary, Pharmacy Network, and Pricing Information Files — Monthly file 2026-10-15 (plan year 2027), file 2027_20261008.zip (data.cms.gov dataset ed1496ea-23e7-41f1-9292-172fa842ccfb): basic drugs formulary file + plan information file, both dated 20261031 inside the zip; downloaded and aggregated 2026-10-30. Medication RxCUI sets resolved through the NLM RxNav (RxNorm) API.

What you pay

Without insurance, the cash benchmark is 0.44633 per unit (URSODIOL 250 MG TABLET) — about nan for 30 units. NADAC benchmark — the average price pharmacies pay (CMS, as of 2026-11-04). Pharmacy shelf prices vary.

A tier is not a price; what you pay depends on your plan, pharmacy, and benefit stage; Extra Help or Medicaid can lower it further.

Sources: CMS Plan Benefit Package + formulary data; CMS NADAC · Checked 2026-11-08

Coverage by plan and tier

Of the 5,495 Medicare drug plans we track for 2027, 5,495 list Ursodiol (Actigall, Urso, and others) — 100% of plans. Most of those plans put it on Tier 3: 2,605 plans, 47.4% of the plans that list it. Other plans place it on Tier 4 (2,224 plans), Tier 2 (511 plans) or Tier 1 (155 plans). For example: Aetna Medicare Dual Extra (HMO D-SNP) puts it on Tier 4; Aetna Medicare Dual Extra Care (PPO D-SNP) puts it on Tier 4; Aetna Medicare Value Plus (PPO) puts it on Tier 4. You can compare these plans side by side on our Medicare Advantage hub. A tier is not a price. What you pay also depends on whether you have met your plan';s deductible, whether the drug costs a flat copay or a share of the price, and whether you get Extra Help or Medicaid.

Read next

• Part D in 2027: The $700 Deductible, the $2,400 Cap, and the $35 Insulin Rule
• Extra Help in 2027: Lower Drug Copays and Who Qualifies
• Checking Medicare Savings Programs and Extra Help

Part D spending averages (2024)

Source: CMS Medicare Part D Spending by Drug (Drug Spending Dashboard), release RY26 P04 V10, data through 2024 (DSD_PTD_RY26_P04_V10_DY24_BGM.csv), downloaded 2026-10-30

Companies covering this drug

Part D and Medicare Advantage plan sponsors that list this drug on a formulary, 50 at a time.