Ursodeoxycholic acid (Ursodiol)
3Ξ±,7Ξ²-dihydroxy-5Ξ²-cholan-24-oic acid
Also known as: Ursodiol Β· Cholurso Β· Destolit Β· Ursofalk Β· Actigall Β· UDCA
Reviewed by the VetSheet Veterinary TeamUpdated Apr 5, 2026Evidence-based veterinary reference
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Dosing by species
π NA β North Americaπ EU β Europe
Dogs
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Hepatobiliary disease / Cholestasis | 10-15 mg/kg | PO | q24h or divided q12h | Long-term | π EU |
- Hepatobiliary disease / Cholestasis: Administer with food to enhance absorption.
Cats
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Hepatobiliary disease / Cholangitis | 10-15 mg/kg | PO | q24h or divided q12h | Long-term | π EU |
- Hepatobiliary disease / Cholangitis: Administer with food to enhance absorption.
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Overview
Ursodeoxycholic acid (UDCA), also known as ursodiol, is a relatively hydrophilic bile acid used primarily for its cytoprotective effects in the biliary system. It protects hepatocytes from toxic hydrophobic bile acids, stimulates bile flow (choleretic), and has immunomodulatory and anti-apoptotic properties.
βClinical Pearl:β Highly effective in the management of chronic hepatitis, cholangitis, and gallbladder sludge.
βWarning:β Contraindicated in patients with complete biliary obstruction.
Mechanism of action
UDCA is a hydrophilic bile acid that inhibits ileal absorption of toxic, hydrophobic bile acids β reduces their concentration in the systemic bile acid pool. Hydrophobic bile acids are toxic to hepatobiliary cell membranes and potentiate cholestasis. UDCA also stimulates biliary secretion (choleretic effect), protects hepatocyte membranes from detergent effects, and exerts immunomodulatory and anti-apoptotic effects on liver cells.
Safety & warnings
Contraindications
- Complete extrahepatic biliary obstruction
- Biliary fistulas
- Severe acute hepatitis
- Cholecystitis
Adverse effects
- Mild gastrointestinal upset (diarrhea, vomiting)
- Hepatotoxicity (rare, typically only if administered during biliary obstruction)
Precautions
βDo not use in patients with complete extrahepatic biliary obstruction.β
Use with caution in patients with complications of advanced liver disease (e.g., ascites, hepatic encephalopathy).
Drug interactions
May bind to UDCA in the GI tract, decreasing its absorption and efficacy.
Binds to UDCA, significantly decreasing its absorption.
Binds to UDCA, significantly decreasing its absorption.
Monitoring
- Liver enzymes (ALT, AST, ALP, GGT)
- Total bilirubin
- Serum bile acids
- Clinical signs of liver disease (jaundice, vomiting, lethargy)
Pharmacokinetics
Half-life
Absorption
Well absorbed from the small intestine (primarily the ileum). Absorption is enhanced when administered with food.
Distribution
Extracted by the liver from portal blood and enters the enterohepatic circulation. Very little reaches systemic circulation.
Metabolism
Conjugated in the liver with glycine or taurine, then secreted into bile.
Elimination
Excreted primarily in feces. Unabsorbed drug is degraded by colonic bacteria.
Overdose
Acute overdosage is unlikely to cause severe toxicity but may result in diarrhea. Treatment is symptomatic and supportive.
Available products
Formulations
- Oral: 150 mg tablet
- Oral: 250 mg tablet
- Oral: 300 mg tablet
- Oral: 500 mg tablet
- Oral: 250 mg capsule
- Oral: 50 mg/ml suspension
Veterinary
- Cholurso
- Ursofalk (often used in veterinary practice)
Human-labeled
- Destolit
- Ursofalk
- Ursodeoxycholic acid generic tablets/capsules/suspension
Regulatory status
Approved for human use; used extra-label in veterinary medicine.
Available as POM (Prescription Only Medicine).
Available as POM-V.
No regulatory data for: ππ° HK Β· πΉπΌ TW Β· π―π΅ JP Β· π°π· KR Β· π¦πΊ AU
Storage & stability
Store at room temperature in tight, light-resistant containers. Keep liquid suspensions well-sealed.
Client information
Give this medication with food to help your pet absorb it better. Do not give at the same time as antacids containing aluminum. Monitor your pet for diarrhea or worsening jaundice (yellowing of the gums or eyes).
βContact your vet if your pet stops eating, vomits repeatedly, or becomes extremely lethargic.β
VetSheet drug reference is intended for licensed veterinary professionals as a clinical decision-support aid, not a substitute for professional judgement or the manufacturerβs current label.