Is Dihexa Safe? Examining Its Benefits, Side Effects, and Warnings Lately I've been getting a lot of questions about cognitive support so I started testing a few things myself. One that's stood out is Dihexa, a peptide that works at the level Dihexa & Tesofensine Bundle Pack: Amazon.com: Industrial & Scientific Dihexa (also known as PNB 0408) is an experimental small molecule derived from angiotensin IV. It was engineered to cross the bloodbrain barrier and has shown synaptogenic effects in preclinical models. The often quoted