dementia and Parkinson's disease drugs

Question 1

Anticholinesterase inhibitors: donepezil

Answer 1

Indication: mild to severe Alzheimer disease

• Mechanisms of action: increases acetylcholine levels in the synapse by inhibiting the enzyme acetylcholinesterase and slowing the degradation of acetylcholine released in cholinergic neurons
• Desired effects: decreased symptoms of Alzheimer disease. Aimed to improve function in 3 domains: ADLs, behaviour and cognition

Question 2

Anticholinesterase inhibitors: donepezil

adverse effects

Answer 2

Adverse effects: vomiting, diarrhea, darkened urine, insomnia, syncope, headache, irritability, headache, fatigue, chest pain, dehydration, and blurred vision

Question 3

NMDA (N-Methyl-D-Aspartate receptor antagonists): memantine

Answer 3

• Indication: Moderate to severe dementia in Alzheimer disease
• Mechanisms of action: Antagonist action of CNS NMDA receptors that may contribute to the symptoms of Alzheimer disease
• Desired effects: Improved mood, orientation, decreasing confusion

Question 4

NMDA (N-Methyl-D-Aspartate receptor antagonists): memantine-adverse effects

Answer 4

Adverse effects: Dizziness, confusion, headache, hypertension, vomiting, constipation, diarrhea, anemia, rash, back pain, fatigue

Question 5

Dopa decarboxylase inhibitors: carbidopa & levodopa

Answer 5

Indication: Parkinson disease
Mechanisms of action:
-Can enter the blood brain barrier
As a precursor to dopamine, levodopa crosses the blood-brain barrier (BBB) and is converted to dopamine.
-Cannot enter blood brain barrier
-Carbidopa functions to decrease the metabolism of levodopa to dopamine which allows levodopa to be more available to enter the brain.
-Dopamine cannot enter the blood-brain barrier, hence, why dopamine therapy is not used.
-Desired effects: absence of involuntary movements
carbidopa helps w/ the movement of levodopa