Tacrine is a centrally acting acetylcholinesterase inhibitor and indirect cholinergic agonist (parasympathomimetic).

It was the first centrally acting cholinesterase inhibitor approved for the treatment of Alzheimer's disease, and was marketed under the trade name Cognex.

[2] Tacrine was the prototypical cholinesterase inhibitor for the treatment of Alzheimer's disease.

[10] As stated above, overdosage of tacrine may give rise to severe side effects such as nausea, vomiting, salivation, sweating, bradycardia, hypotension, collapse, and convulsions.

[12] Major form of metabolism is in the liver via hydroxylation of benzylic carbon by CYP1A2.