TUDCA (Tauroursodeoxycholic Acid)
TUDCA is the taurine conjugate of ursodeoxycholic acid, a hydrophilic bile acid marketed as a liver-support supplement. PED users take it primarily on oral 17-alpha-alkylated steroid cycles to relieve cholestasis — the bile-flow impairment that drives raised bilirubin, jaundice and itching. Human evidence for its use in AAS-induced cholestasis is largely anecdotal and extrapolated from cholestatic-liver-disease trials of its parent compound UDCA.
01 Overview
TUDCA works as a choleretic: it expands the hydrophilic bile-acid pool, displacing more toxic hydrophobic bile acids, stabilising hepatocyte membranes and stimulating bile flow. This is the same mechanistic basis on which UDCA (ursodiol) is licensed for primary biliary cholangitis and gallstone dissolution. TUDCA additionally has documented ER-stress-reducing (chemical chaperone) activity in preclinical models.
Among PED users it is taken during methylated oral cycles to counter the intrahepatic cholestasis those compounds cause, and to lower elevated bilirubin. It does not meaningfully protect against the transaminase elevations or the rare peliosis/adenoma risk of oral AAS, and its dosing in this population is derived from anecdote rather than trials. It is generally very well tolerated, with loose stools the main complaint.
02 Mechanism
Hydrophilic bile acid that enriches the bile-acid pool with less cytotoxic species, stabilises hepatocyte and mitochondrial membranes, promotes bile flow (choleresis) and acts as a chemical chaperone reducing endoplasmic-reticulum stress.
03 Dosing
| Tier | Dose | Route | Notes |
|---|---|---|---|
| Parent UDCA cholestasis dosing (reference) | 13–15 mg/kg/day | Oral | Licensed ursodiol dose for primary biliary cholangitis, for context only. |
| General liver support | 250–500 mg/day | Oral | Common maintenance range used alongside non-methylated cycles. |
| On methylated orals | 500–1000 mg/day | Oral | Anecdotal dosing to counter cholestasis from 17aa oral steroids; split through the day. |
04 Effects
| Effect | Magnitude | Evidence | |
|---|---|---|---|
| Improved bile flow / lower bilirubinRelieves cholestasis and can lower elevated bilirubin; strongest evidence is for the parent UDCA in cholestatic liver disease. | variable | Observational | |
| Relief of cholestatic itchUsers report reduced pruritus and jaundice on methylated orals, consistent with restored bile flow. | subjective | Anecdotal |
05 Side effects
| Effect | Severity | Frequency | Evidence | Countermeasures |
|---|---|---|---|---|
| Diarrhoea / loose stoolsThe most frequent complaint; dose-related loosening of stool. | Mild | Common | Observational | |
| False sense of hepatic safetyTUDCA addresses cholestasis but not transaminase-marked hepatocellular stress or structural lesions from oral AAS, so users may run harsh orals longer than is safe. | Moderate | Situational | Anecdotal |