alzheimer's

Question 1

Donepezil (Aricept)

Answer 1

• reversible AChE inhibitor
• tx: severe AD (only one that treats all stages of AD)
• metabolized by CYP2D6 and 3A4
• once daily dosing
• SE: N+V, diarrhea

Question 2

Galantamine

Answer 2

• reversible, competitive AChE inhibitor (some nicotinic effects too)
• mild-mod alzheimer’s
• CYP2D6 and 3A4
• contraindicated in renal, liver dysfunction
• SE: N+V, diarrhea, dizziness, anorexia and weight loss
• adverse effects with dose escalation

Question 3

Rivastigmine

Answer 3

• reverisible, non competitive inhib of AChE
• mild-mod dementia of AD and Parkinson’s
• metabolism: hydrolysis by esterases –> not metabolized by CYP450’s so no drug interactions
• transdermal patch may be used (more reliable in AD PTs)
• SE: N+V, diarrhea (less with transdermal patch)

Question 4

Tacrine

Answer 4

• 1st AChE inhibitor
• mild-mod AD
• 4 times daily dosing and hepatotoxicity –> not really used anymore

Question 5

Memantine (Namenda)

Answer 5

• NMDA antagonist
• mod-severe AD, use as adjunct to AChE ihibitors
• prevent glutamine overstimulation and toxicity
• excreted unchanged in urine –> no dosing adjustments needed for PTs with mild-mod renal impaiment
• drug interaction with amantadine (competition at NMDA receptor)
• SE: dizzinness, hallucinations, insomnia, confusions, delusions