Tauroursodeoxycholic acid (TUDCA)

Bile acid, conjugate of ursodeoxycholic acid with taurine. RX medicine in Japan; in EU/US sold as supplement. AEMPS does not register it as a medicine. Not registered in Russia via GRLS

ATC code: A05AA-TUDCA

Brand names – supplements: Now TUDCA, Double Wood TUDCA, Nutricost TUDCA, Jarrow Formulas TUDCASupplements are not tested in clinical trials and are not registered as medications.

Updated 19 Jun 2026 · Methodology

Marketing claims without evidence base

The drug is promoted for these uses outside international guidelines. Each entry below is analyzed against AEMPS, FDA, EMA, Cochrane and major RCTs.

Anti-aging and longevity

Not recommended

Tauroursodeoxycholic acid (TUDCA) is a bile acid. Researchers study it in liver and bile-duct conditions, and the biohacking scene promotes it as a supplement to slow aging and extend lifespan. Convincing benefit for that specific purpose has not been shown in people: there are no quality clinical trials on TUDCA taken for longevity. What actually affects how long and how well people live are well-established habits, namely enough sleep, regular physical activity, a diet low in ultra-processed food, not smoking, and keeping blood pressure, glucose, and weight in check.

Sources

Cell Mol Biol: Tauroursodeoxycholic acid: an emerging therapeutic agent in hepatic and metabolic disease (2014)

Non-alcoholic fatty liver disease

Not recommended

TUDCA is sold in the biohacking segment as a «gold standard liver shield» for non-alcoholic fatty liver disease (NAFLD/MASLD). Human evidence base is small: isolated small phase II RCTs in 20–40 patients showed improved insulin sensitivity and reduced endoplasmic reticulum stress markers, but hard outcomes (fibrosis, portal hypertension, liver mortality) were not assessed. 2023 and --EASO 2024 list as first-line in NAFLD/MASLD: 7–10% weight loss, Mediterranean diet and physical activity; confirmed NASH includes resmetirom (Rezdiffra, 03/2024), pioglitazone in T2DM, GLP-1 receptor agonists semaglutide. TUDCA is not in NAFLD international guidelines. If TUDCA was recommended for NAFLD instead of dietary correction, physical activity and workup (, lipid panel, FibroScan), consider seeking a second opinion from a hepatologist.

Sources

ICD-10: K76.0 · ICD-11: DB92

How to read tiers A–F

AStrong evidence – first or second line in international guidelines
BRecommended in selected cases
CStudy data contradict each other
DBenefit not proven, no documented harm
FDocumented harm, or risk without benefit

Mechanism of action

TUDCA is a taurine conjugate of ursodeoxycholic acid, a hydrophilic bile acid physiologically present in bears at high concentration. Mechanisms: displaces toxic hydrophobic bile acids (chenodeoxycholic, lithocholic) from the pool, reducing their hepatotoxicity; inhibits hepatocyte apoptosis via mitochondrial membrane stabilisation; reduces endoplasmic reticulum stress through PERK-eIF2α pathway suppression; modulates FXR signalling. Clinical evidence base is small: used in Japan for primary biliary cholangitis as a ursodeoxycholic acid alternative (over 30 years, limited RCTs); other indications at phase II and observational data. AEMPS has not registered it as a medicine in Spain.

Safety

Contraindications

Pregnancy and lactation
Children under 18
Acute cholecystitis, gallbladder empyema, calcified gallstones
Bile and pancreatic duct obstruction
Severe hepatic failure
Ciprofloxacin, moclobemide, phenytoin therapy (reduced bioavailability of interacting drugs)

Serious adverse effects

Calcification of radiolucent gallstones (becoming radiopaque)
Biliary colic and gallstone disease exacerbation
Decompensation in cirrhotic stage of primary biliary cholangitis

Common adverse effects

Diarrhoea (especially at doses ≥500 mg/day)
Nausea
Right upper quadrant pain
Skin itching

Pregnancy: can you take Tauroursodeoxycholic acid (TUDCA)?

No RCT data in pregnancy. AEMPS does not register it as a medicine, so no official category. Avoid in pregnancy. Ursodeoxycholic acid (close analogue) is used in intrahepatic cholestasis of pregnancy under obstetric supervision; no such data for TUDCA.

Breastfeeding: can you take Tauroursodeoxycholic acid (TUDCA)?

No data on milk transfer. Lactating women should avoid.

Calculate RID

Reference information, not a clinical decision. Discuss feeding pauses or changes with your physician or an IBCLC.

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Frequently asked

What is Tauroursodeoxycholic acid (TUDCA) used for?

Tauroursodeoxycholic acid (TUDCA) is evaluated for the following indications with varying evidence strength: Non-alcoholic fatty liver disease (evidence tier D), Anti-aging and longevity (evidence tier D). See the full indication matrix with dosing and citations above on this page.

What are the side effects of Tauroursodeoxycholic acid (TUDCA)?

Common side effects of Tauroursodeoxycholic acid (TUDCA) (≥ 1 in 100): Diarrhoea (especially at doses ≥500 mg/day), Nausea, Right upper quadrant pain, Skin itching. See the Safety section for uncommon and serious reactions.

Is Tauroursodeoxycholic acid (TUDCA) safe during pregnancy?

Is Tauroursodeoxycholic acid (TUDCA) compatible with breastfeeding?

No data on milk transfer. Lactating women should avoid.

Who should not take Tauroursodeoxycholic acid (TUDCA)?

Tauroursodeoxycholic acid (TUDCA) is contraindicated in: Pregnancy and lactation; Children under 18; Acute cholecystitis, gallbladder empyema, calcified gallstones; Bile and pancreatic duct obstruction; Severe hepatic failure. Full list in the Safety section.

Other drugs in this group

Essential phospholipids, Glycyrrhizic acid + phospholipids, L-ornithine-L-aspartate (LOLA), Silymarin (Silybum marianum), Ursodeoxycholic acid