Classification and mechanism of action of alzheimers drugs

Classification and mechanism of action of alzheimers drugs

1. CLASSIFICATION AND MECHANISM OF ACTION OF ALZHEIMER’S DRUGS Presented by :- Sajal kumar Chowdhury B.PHARM 4 TH YEAR

2. WHAT IS ALZHEIMER’S Alzheimer’s is the most common form of dementia . It is neurodegenerative disease that occurs in brain . Alzheimer’s diseases causes a deterioration in the brain by destroying the nerve cells . Once the nerve cells begin to deteriorate it cases a reduction of responses to other nerve cells

3. SYMPTOMS OF ALZHEIMER’S Short term memory loss Difficulty performing familiar tasks Increasing problems with planning and managing Trouble with language Rapid mood swings Lack of motivation Changes in sleep about the time of day Reduce judgement

4. CLASSIFICATION OF ALZHEIMER’S DRUGS Approve Drugs 1.Cholinesterase:- A . Doepezil B . Rivastigmine C . Galantamine 2 . NMDA Antagonist:- Memantine

5. MECHANISM OF ACTION OF MEMANTINE Memantine is a clinically useful drug in many neurological disorders, including Alzheimer’s disease. The principal mechanism of action of memantine is believed to be the blockade of current flow though channels of N-methyl-d-aspartate (NMDA) receptors –a glutamate receptor subfamily broadly involved in brain function. Surprisingly, other drugs that block NMDA receptor channels, such as ketamine, exhibit serious deleterious effects. The unusual therapeutic utility of memantine probably results from inhibitory mechanisms shared with ketamine, combined with actions specific to memantine. These potentially important differences between memantine and ketamine include effects on gating of blocked channels & binding of memantine to two sites on NMDA receptors.

6. MECHANISM OF ACTION OF TACRINE 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.

7. MECHANISM OF ACTION OF GALANTAMINE Galantamine is a phenanthrene alkaloid and a reversible , competitive acetylcholinesterase inhibitor it is not structurally related to other acetylcholinesterase inhibitors . Galantamine’s proposed mechanism of action involves the reversible inhibition of acetylcholine, leading to an increased concentration of acetylcholine at cholinergic synapses. Galantamine also binds allosterically with nicotinic acetylcholine receptors and may possibly potentiate the action of agonists (such as acetylcholine ) at these receptors.

8. References http://en.wikipedia.org/wiki/Galantamine http://en.wikipedia.org/wiki/Donepezil http://en.wikipedia.org/wiki/Mementine http://en.wikipedia.org/wiki/Mementine Hospital and Clinical Pharmacy , Randhir Singha Dahiya and Dinesh Luther, Nirmala Prakashan

9. Thank you