TUDCA & The Liver

TL:DR Useful compound for reducing liver stress on cycle.

A post in the /r/PEDs quick question thread prompted this article, where a long distance runner, not currently on cycle, was seeking advice about improving liver values on a blood test so they could donate blood (and save lives like a goddamn hero). TUDCA has a range of potential therapeutic uses, but this is specific only to liver protection.

What is TUDCA?

Tauroursodeoxycholic acid (TUDCA) is an acid found in bile, and found in large quantities in bears. Bile is created in the liver, and helps the small intestine digest food. TUDCA was synthetically created in 1954, and western medicine became subsequently interested in its effects (ain’t nobody want to be hunting bears to obtain some TUDCA), though it has to be said that animal bile has been used by the Chinese for a long time to relieve spasms, fever and improve vision.

What Causes Liver Values To Change?

17 alpha alkylated steroids are (usually) taken orally and metabolized in the liver. The slow clearance of these compounds makes them hepatotoxic, characterized by elevated liver transaminases (ALT, AST), acute cholestatic syndrome, chronic vascular injury, hepatic tumors, changes in lipoproteins and toxicant-associated fatty liver disease.

Examples of 17 alpha alkylated steroids include fluoxymesterone, methyltestosterone, oxandrolone, stanozolol. A comprehensive list is available here.

ALT and AST are good markers for detecting inflammation, and easy to detect. However, these markers don’t just show liver inflammation, and muscle inflammation can elevate them too. In the original scenario a long distance runner, or a weight lifter for that matter, can have unusually high ALT and AST. The way to distinguish between muscular inflammation or genuine hepatic distress is the ratio of the two - AST should be approximately 0.8 of ALT level (AST * 0.8 = ALT). Once elevated from muscular inflammation, levels can be expected to stay elevated for about a week.


Study 1: 27 patients with chronic hepatitis and liver markers at least twice the upper limit of normal (normal is 7-56U/L, so at least 112U/L to qualify for this study) took TUDCA 500mg/day, split into an AM/PM dose, with an additional 26 patients serving as control. Within a month, there was a statistically significant change in liver values, and by month 3 had lowered AST by 44%, ALT by 49%, and GGT by 38%.

Study 2: 23 patients with liver cirrhosis were divided into groups that received TUDCA (n=12) or UDCA (n=11), and received a daily dose of 750mg for 6 months. ALT, AST and ALP levels in TUDCA group were significantly reduced, while UDCA reduced only AST. Albumin was slightly increased, and other liver fibrosis markers only slightly decreased.

The conclusion drawn from Study 1 & 2 is that while TUDCA does improve AST and ALT, it does not necessary result in recovery of the liver itself should it be damaged. I interpret this as TUDCA reducing inflammation and stress on the liver, but not necessarily healing it. It’s too early to tell for sure.

Examine.com has a couple of references on this, citing that TUDCA suppresses stress on the liver (specifically endoplasmic reticulum which regulates inflammation among other things).

Study 3: 24 patients received 500,1000, or 1500mg daily of TUDCA for 6 months. HDL significantly decreased, as did AST, ALT and GGT. Researchers concluded by regression analysis that optimal dose is 10-15mg/kg of body weight.

Dose & Side Effects

Study 3 shows us that for a 90kg / 200 pound male, 900mg-1350mg daily is an optimal dose. Dose is not gender specific - both men and women can use TUDCA.

TUDCA has no adverse effects up to 1500mg with the only reported side effect I could find being diarrhea. However, high doses for long period of time may be toxic (specifically for those with primary sclerosing cholangitis).


Preventing elevated liver enzymes and reducing liver stress when using alkylated oral steroids seems the most obvious time to include TUDCA. It also will have benefit during times of bodily stress and inflammation, such as running or when undergoing significant muscle growth such as we do when using PEDs. 500mg-1000mg, depending on weight, seems to be about right for most people.