Dementia Drugs

Question 1

Dementia is a general term for loss of memory, language, problem-solving and other thinking abilities that are severe enough to interfere with daily life. There are a number of diagnosis that come under the dementia umbrella including Alzheimers Disease, Vascular dementia, Lewy body disorders and Fronto-temporal dementia. In some of these forms of dementia there tends to be reduced cholinergic activity in cortex, specifically acetylcholine (ACh), resulting in low levels of ACh. Donepezil is a core drug that is used to treat Alzheimers only, but not other dementias. What is the mechanism of action of this drug?

1 - increases vesicles containing ACh to be released into pre synaptic cleft
2 - ACh receptor agonist
3 - inhibitor of cholinesterase and degrades acetylcholinesterase
4 - binds reversibly to acetylcholinesterase

Answer 1

4 - binds reversibly to acetylcholinesterase

• inhibits the hydrolysis of ACh
• increases ACh and cholinergic activity

Question 2

Dementia is a general term for loss of memory, language, problem-solving and other thinking abilities that are severe enough to interfere with daily life. There are a number of diagnosis that come under the dementia umbrella including Alzheimers Disease, Vascular dementia, Lewy body disorders and Fronto-temporal dementia. In some of these forms of dementia there tends to be reduced cholinergic activity in cortex, specifically acetylcholine (ACh), resulting in low levels of ACh. What can Memantine do to help treat dementia, specifically Alzheimers Disease?

Answer 2

• memantine is an NMDA receptor antagonist
• high levels of glutamate through NMDA binding is linked with neurotoxicity in Alzheimers Disease
• neurotoxicity is linked with increased levels of B-amyloid

Question 3

Memantine is a drug that is used to treat mild to moderate Alzheimers disease. What is its mechanism of action?

1 - NMDA antagonist, reducing glutamate binding
2 - NMDA agonist, increasing glutamate binding
3 - inhibitor of cholinesterase and degrades acetylcholinesterase
4 - binds reversibly to acetylcholinesterase

Answer 3

1 - NMDA antagonist, reducing glutamate binding

Question 4

Memantine is a drug that is used to treat mild to moderate Alzheimers disease, acting as a NMDA antagonist, reducing glutamate binding. Why is this important in Alzheimers?

Answer 4

• glutamate continues to be released, even in neuronal cell death in Alzheimers
• excess levels of glutamate results in over-excitation of nerve cells
• over-excitation leads to excitotoxicity and cell death