RP Pharmacology Fundamentals 2 — Questions and Answers
Question 1: A client on an SSRI reports onset of restlessness, agitation, and muscle twitching after their physician added tramadol. Which condition is most likely occurring?
- Neuroleptic malignant syndrome
- Serotonin syndrome (Correct answer)
- Anticholinergic toxicity
- Extrapyramidal side effects
Correct answer: Serotonin syndrome
Combining SSRIs with tramadol (which inhibits serotonin reuptake) can precipitate serotonin syndrome, characterized by agitation, autonomic instability, and neuromuscular abnormalities.
Question 2: Which class of medications works by blocking dopamine D2 receptors and is most associated with tardive dyskinesia with long-term use?
- Benzodiazepines
- Mood stabilizers
- First-generation antipsychotics (Correct answer)
- SNRIs
Correct answer: First-generation antipsychotics
First-generation (typical) antipsychotics block D2 receptors and are strongly associated with tardive dyskinesia, an involuntary movement disorder, after prolonged use.
Question 3: A client taking lithium develops coarse tremor, polyuria, and confusion. Serum lithium is 2.4 mEq/L. What is the priority clinical concern?
- Lithium discontinuation syndrome
- Sub-therapeutic dosing
- Lithium toxicity (Correct answer)
- Hypothyroidism
Correct answer: Lithium toxicity
Lithium levels above 1.5 mEq/L indicate toxicity; levels above 2.0 mEq/L are severe and require immediate medical intervention.
Question 4: Which pharmacokinetic process describes the conversion of an active drug into inactive metabolites, primarily occurring in the liver?
- Absorption
- Distribution
- Biotransformation (metabolism) (Correct answer)
- Excretion
Correct answer: Biotransformation (metabolism)
Biotransformation (metabolism) converts drugs into metabolites, mostly via hepatic CYP450 enzymes, often rendering them inactive for excretion.
Question 5: A client is prescribed a medication with a half-life of 24 hours. Approximately how long will it take to reach steady-state plasma concentration?
- 24 hours
- 48 hours
- 4–5 days (Correct answer)
- 10–14 days
Correct answer: 4–5 days
Steady state is typically reached after approximately 4–5 half-lives, so a drug with a 24-hour half-life reaches steady state in about 4–5 days.
Question 6: Which of the following best describes a drug that competes with the endogenous ligand at a receptor site but produces no intrinsic effect?
- Full agonist
- Partial agonist
- Competitive antagonist (Correct answer)
- Inverse agonist
Correct answer: Competitive antagonist
A competitive antagonist binds to the same receptor site as the endogenous ligand and blocks its action without producing a response itself.
Question 7: When a psychotherapist notices a client on warfarin has been prescribed fluconazole by another provider, what interaction concern is most critical to communicate to the prescriber?
- Fluconazole decreases warfarin absorption
- Fluconazole inhibits CYP2C9 and may increase warfarin levels, raising bleeding risk (Correct answer)
- Fluconazole induces warfarin metabolism and reduces anticoagulant effect
- The two drugs compete for plasma protein binding with no clinical effect
Correct answer: Fluconazole inhibits CYP2C9 and may increase warfarin levels, raising bleeding risk
Fluconazole inhibits CYP2C9, the primary enzyme metabolizing warfarin, leading to elevated warfarin levels and significantly increased bleeding risk.
RP Pharmacology Fundamentals 2
A client on an SSRI reports onset of restlessness, agitation, and muscle twitching after their physician added tramadol.
Which condition is most likely occurring?