VelnacrineVelnacrine, also known as 1-hydroxytacrine, is an inhibitor of cholinesterase enzymes. It is also a metabolite of tacrine.PharmacologyVelnacrine is able to inhibit acetylcholinesterase, this results in elevated levels of acetylcholine, as AChE is the enzyme that hydrolyzes acetylcholine. It is also able to inhibit butyrylcholinesterase.Therapeutic potentialVelnacrine, as many other cholinergics, has been described as possibly useful to help manage symptoms of Alzheimer's disease. Some research has described the drug as having benefits over placebo and an acceptable safety profile. However, a review described available data as not proving efficacy and showing evidence of toxicity. Additionally, the FDA voted against recommending approval of velnacrine.