Tauroursodeoxycholic Acid
Useful mainly for investigational use in cholestatic liver disease and ALS; not a routine supplement.
Quick decision guide
May help most
investigational use in cholestatic liver disease and ALS; not a routine supplement
Common dosing range
500–1500 mg/day, divided with meals
When to expect effects
Weeks to months
Watch out for
Contraindicated in complete biliary obstruction; loose stools are common
What is it
Tauroursodeoxycholic acid (TUDCA) is the taurine-conjugated form of ursodeoxycholic acid (UDCA), a naturally occurring hydrophilic bile acid found in small amounts in human bile and historically isolated from bear bile in traditional East Asian medicine. Chemically (C26H45NO6S), it behaves as a chemical chaperone that stabilises protein folding in the endoplasmic reticulum, reducing ER stress and the unfolded protein response, while also exerting anti-apoptotic effects via inhibition of the mitochondrial permeability transition and Bax translocation. In the liver, TUDCA expands the hydrophilic bile-acid pool and competitively displaces cytotoxic hydrophobic bile acids (such as deoxycholic and chenodeoxycholic acid) from hepatocyte membranes, which underlies its hepatoprotective and choleretic activity.
Is it worth it for you?
Use this as a quick fit check, not a diagnosis.
Worth considering if…
Probably skip if…
Evidence at a glance
| Goal | Effect | Best fit | Time |
|---|---|---|---|
amyotrophic lateral sclerosis (ALS) Limited Evidence | Slowed functional decline in a combination trial | people with ALS, under specialist care | Months |
amyotrophic lateral sclerosis (ALS)
- Effect
- Slowed functional decline in a combination trial
- Best fit
- people with ALS, under specialist care
- Time
- Months
Evidence for 1 use
AI-assisted evidence assessment — talk to your doctor before relying on any single supplement.
amyotrophic lateral sclerosis (ALS)
Disease adjunctTUDCA acts as a chemical chaperone that reduces ER stress and apoptosis, and a randomized trial of sodium phenylbutyrate plus TUDCA slowed functional decline in ALS, though a later larger phase 3 trial of that combination did not confirm benefit. Because the positive data come from a combination product, the independent effect of TUDCA is uncertain. It remains investigational and specialist-directed.
Bottom line: TUDCA, in a phenylbutyrate combination, showed promise in ALS but later trials were not confirmatory.
Evidence is mixed
An earlier combination trial slowed ALS decline, but a larger phase 3 trial of the same combination failed to confirm benefit, and TUDCA's solo effect is unclear.
How to take it
What to track
Safety
Know the common side effects, key cautions, and who should avoid it.
Common side effects
Who should avoid it
- people with complete biliary obstruction
- those with acute cholecystitis or radiopaque gallstones without supervision
Pregnancy & breastfeeding
Supplemental TUDCA is not recommended in pregnancy or breastfeeding outside medical supervision.
Interactions
bind TUDCA in the gut and reduce absorption; separate by several hours
impair TUDCA absorption
Choosing a product
What to look for on the label — and what to be skeptical of.
Look for…
Be skeptical of…
References by claim
Track Tauroursodeoxycholic Acid with Pilora
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Coming to App StoreDisclaimer: These statements have not been evaluated by the FDA. This page is educational, not a substitute for personalized medical advice. Evidence grades are AI-assisted assessments — talk to your doctor before starting any new supplement, especially if you’re pregnant, breastfeeding, on medications, or managing a chronic condition.