[This article was originally published on Dan Elton's blog, More is Different.] Cerebrolysin is an unregulated medical product made from enzymatically digested pig brain tissue. Hundreds of scientific papers claim that it boosts BDNF, stimulates neurogenesis, and can help treat numerous neural diseases. It is widely used by doctors around the world, especially in Russia and China. A recent video of Bryan Johnson injecting Cerebrolysin has over a million views on X and 570,000 views on YouTube. The drug, which is advertised as a “peptide combination”, can be purchased easily online and appears to be growing in popularity among biohackers, rationalists, and transhumanists. The subreddit r/Cerebrolysin has 3,100 members. TL;DR Unfortunately, our investigation indicates that the benefits attributed to Cerebrolysin are biologically implausible and unlikely to be real. Here’s what we found: * Cerebrolysin has been used clinically since the 1950s, and has escaped regulatory oversight due to some combination of being a “natural product” and being grandfathered in. * Basic information that would be required for any FDA approved drug is missing, including information on the drug’s synthesis, composition, and pharmacokinetics. * Ever Pharma’s claim that it contains neurotrophic peptides in therapeutic quantities is likely false. HPLC and other evidence show Cerebrolysin is composed of amino acids, phosphates, and salt, along with some random protein fragments. * Ever Pharma’s marketing materials for Cerebrolysin contain numerous scientific errors. * Many scientific papers on Cerebrolysin appear to have ties to its manufacturer, Ever Pharma, and sometimes those ties are not reported. * Ever Pharma’s explanation of how the putative peptides in Cerebrolyin cross the blood-brain barrier does not make sense and flies in the face of scientific research which shows that most peptides do not cross the blood-brain barrier (including neurotrophic peptides like BDNF, CDNF, and