Tacrine an anticholinesterase drug used primarily in the treatment of Alzheimer's disease, the drug also counters the effects of muscle relaxants, respiratory stimulants and other central nervous disorders. Its mechanism of action is not fully known but is thought that the drug reversibly binds and inhibits cholinesterase and acetylcholinesterase. Stopping the breakdown of acetylcholine leads to cholinergic receptors being further stimulated and accumulating in the synaptic cleft. Tacrine is a parasympathomimetic, meaning it acts as a cholinergic receptor stimulating agent that aids symptoms of mild to moderate dementia as seen in Alzheimer's. Symptoms of memory loss and deficiencies in cognitive function due to a loss of acetylcholine from the lack of cholinergic neurons within the brain. Tacrine should be taken on an empty stomach, at least one hour prior to a meal in order for optimal absorption to take place. It is metabolized by first-pass metabolism by the enzyme Cytochrome P450 1A2 resulting in velnacrine (1-hydroxy-tacrine). If an overdose does occur symptoms such as nausea, vomiting, salivation, sweating, bradycardia, hypotension, fainting and convulsions.

Tacrine Pathway (new) References