Is LGD-4033 liver toxic?
In the spring we already wrote about a bodybuilder who suffered liver damage from a treatment with the SARM LGD-4033. That case study was not convincing per se, as the bodybuilder in question drank a lot of alcohol. But now, doctors at Baylor College of Medicine in the United States are reporting another case of LGD-4033 liver damage. And in this new case study, there are no other explanatory factors...The patient

The protagonist in the case study is a 32-year-old bodybuilder who told doctors that he had used 10 milligrams of LGD-4033 in a liquid form daily for 15 days. After that he had fallen ill and had halted his LGD-4033 cycle. The man had stomach pains and nausea, as well as itching and jaundice. His stools were gray, he had lost his appetite. When he reported to the doctors, the man had already lost 18 kilos.These are classic symptoms of liver damage. Indeed, when the doctors scanned the bodybuilder's abdominal cavity, they noticed that the man's liver was larger than normal. A biopsy showed that the bodybuilder's liver was scarred in places. The channels that transport bile salts to the intestines were closed.
In the weeks that followed, the doctors monitored four markers of liver damage in the bodybuilder's blood. The figure below shows that the man's liver condition slowly improved.

How is that possible?

According to a 2013 trial conducted by the makers of LGD-4033, LGD-4033 is not harmful to the liver. But in this trial, the subjects did not receive more than 1 milligram of LGD-4033 per day.The companies that are selling SARMs on line and some bodybuilding gurus recommend significantly higher doses. For example, the doctors' patient took ten times the highest dose tested in the 2013 trial. Perhaps, the doctors speculate, LGD-4033 in those high doses is taxing on the liver.
Some LGD-4033 users have published thier blood work on internet forums. They don't show indications of liver damage.
Maybe the bodybuilder about which this post is about was using a wrong product. Not all SARMs in online stores are carefully produced, according to recent English and American research. [JAMA. 2017 Nov 28;318(20):2004-10.]
Or maybe he was using other substances than just LGD-4033, and not informing his practitioners about it. Or perhaps LGD-4033 can cause liver damage in one person, but not in another.
ACG Case Rep J 2020;7:e00370.