Review of the acetylcholinesterase inhibitor galanthamine.

Sramek JJ, Frackiewicz EJ, Cutler NR

California Clinical Trials,
8501 Wilshire Boulevard, 2nd Floor
Beverly Hills, CA 90211, USA. jsramek@cctrials.com
Expert Opin Investig Drugs 2000 Oct;9(10):2393-402

Abstract

Galanthamine (or galantamine, Reminyl) is a tertiary alkaloid acetylcholinesterase inhibitor (AChEI) which has been approved in several countries for the symptomatic treatment of senile dementia of the Alzheimer’s type. Derived from bulbs of the common snowdrop and several Amaryllidaceae plants, (-)-galanthamine (GAL) has long been used in anaesthetics to reverse neuromuscular paralysis induced by turbocurarine-like muscle relaxants and more recently, has been shown to attenuate drug- and lesion-induced cognitive deficits in animal models of learning and memory. Galanthamine directly inhibits acetylcholinesterase activity, while demonstrating much weaker activity on butyrylcholinesterase (BuChE). Galanthamine also stimulates pre- and postsynaptic nicotinic receptors, although the clinical significance of this finding is yet unclear. Numerous variants and analogues of galanthamine have also been developed, with varying potency in inhibiting AChE activity. Galanthamine is readily absorbed after oral administration, with a t(max) of 52 min and a plasma elimination t(1/2) of 5.7 h. The efficacy of galanthamine administered to Alzheimer’s disease (AD) patients has been well demonstrated by large-scale clinical trials. Typical of AChEIs, the most common adverse events associated with galanthamine are nausea and vomiting. In conclusion, evidence to date suggests galanthamine to be similar to other AChEIs in improving cognitive function in Alzheimer’s disease patients.