Central Nervous System Agents Flashcards
7 cards from real Pharmacology practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Central Nervous System Agents flashcards as text
A patient taking an MAO inhibitor eats aged cheese and develops a hypertensive crisis. What interaction caused this?
Answer: Tyramine accumulation due to inhibited MAO-A breakdown
MAO-A normally metabolizes dietary tyramine; inhibiting it causes tyramine accumulation, massive norepinephrine release, and hypertensive crisis.
Which benzodiazepine is preferred for treating acute alcohol withdrawal seizures due to its long half-life and self-tapering effect?
Answer: Diazepam
Diazepam has active metabolites with very long half-lives, providing a gradual self-tapering effect ideal for alcohol withdrawal management.
A patient on lithium presents with coarse tremor, confusion, and ataxia. Serum lithium is 2.8 mEq/L. What is the priority intervention?
Answer: Discontinue lithium and initiate hemodialysis
Lithium toxicity above 2.5 mEq/L with neurological symptoms requires immediate discontinuation and hemodialysis to rapidly clear lithium.
Which mechanism best explains how levodopa reduces Parkinson's symptoms?
Answer: Crosses the blood-brain barrier and is converted to dopamine
Levodopa crosses the blood-brain barrier (unlike dopamine) and is decarboxylated to dopamine by DOPA decarboxylase in the CNS.
A nurse administers flumazenil to reverse benzodiazepine sedation. What critical risk must be monitored for?
Answer: Resedation as flumazenil wears off before the benzodiazepine
Flumazenil has a shorter half-life (~1 hour) than most benzodiazepines, so resedation can occur when flumazenil is metabolized.
Which antiepileptic drug acts primarily by blocking voltage-gated sodium channels to stabilize neuronal membranes?
Answer: Phenytoin
Phenytoin blocks voltage-gated sodium channels in the inactive state, preventing repetitive neuronal firing without affecting normal neural activity.
A patient with bipolar disorder is started on valproate. Which baseline lab is most critical before initiating therapy?
Answer: Liver function tests
Valproate is hepatotoxic (especially in children under 2), so baseline LFTs are essential before initiating therapy.