For the palliative treatment of mild to moderate dementia of the Alzheimer's type.
Tacrine is a parasympathomimetic- a reversible cholinesterase inhibitor that is indicated for the treatment of mild to moderate dementia of the Alzheimer's type. An early pathophysiological feature of Alzheimer's disease that is associated with memory loss and cognitive deficits is a deficiency of acetylcholine as a result of selective loss of cholinergic neurons in the cerebral cortex, nucleus basalis, and hippocampus. Tacrine is postulated to exert its therapeutic effect by enhancing cholinergic function. This is accomplished by increasing the concentration of acetylcholine at cholinergic synapses through reversible inhibition of its hydrolysis by acetylcholinesterase. If this proposed mechanism of action is correct, tacrine's effect may lessen as the disease progresses and fewer cholinergic neurons remain functionally intact. There is no evidence that tacrine alters the course of the underlying dementing process.
Mode of Action:
The mechanism of tacrine is not fully known, but it is suggested that the drug is an anticholinesterase agent which reversibly binds with and inactivates cholinesterases. This inhibits the hydrolysis of acetylcholine released from functioning cholinergic neurons, thus leading to an accumulation of acetylcholine at cholinergic synapses. The result is a prolonged effect of acetylcholine.
Hepatic. Cytochrome P450 1A2 is the principal isozyme involved in tacrine metabolism. The major metabolite, 1-hydroxy-tacrine (velnacrine), has central cholinergic activity.
Overdosage with cholinesterase inhibitors can cause a cholinergic crisis characterized by severe nausea/vomiting, salivation, sweating, bradycardia, hypotension, collapse, and convulsions. Increasing muscle weakness is a possibility and may result in death if respiratory muscles are involved. The estimated median lethal dose of tacrine following a single oral dose in rats is 40 mg/kg, or approximately 12 times the maximum recommended human dose of 160 mg/day.
Qizilbash N, Whitehead A, Higgins J, Wilcock G, Schneider L, Farlow M: Cholinesterase inhibition for Alzheimer disease: a meta-analysis of the tacrine trials. Dementia Trialistsê Collaboration. JAMA. 1998 Nov 25;280(20):1777-82. Pubmed Hansen RA, Gartlehner G, Kaufer DJ, Lohr KN, Carey T: Pubmed
Products currently covered by valid US Patents are offered for R&D use in accordance with 35 USC 271(e)+A13(1). Any patent infringement and resulting liability is solely at buyer risk.
API’s From Quality Manufacturers:
Cost effective materials based on specific requirements
Small quantities for initial research and larger development quantities towards product commercialization
Technical packages, letters of access to filed DMFs