AEMCA Pharmacology for Paramedics 5 — Questions and Answers
Question 1: A patient on chronic lithium therapy presents with nausea, tremor, and altered mental status. This presentation is most consistent with:
- Lithium therapeutic level
- Lithium toxicity (Correct answer)
- Serotonin syndrome
- Neuroleptic malignant syndrome
Correct answer: Lithium toxicity
Tremor, nausea, and AMS are classic signs of lithium toxicity, which has a narrow therapeutic index and is worsened by dehydration.
Question 2: Which opioid analgesic has the longest duration of action and highest risk for prolonged respiratory depression?
- Fentanyl
- Hydromorphone
- Methadone (Correct answer)
- Morphine
Correct answer: Methadone
Methadone has an extremely long half-life (24-36+ hours), putting patients at risk for delayed respiratory depression after initial dosing.
Question 3: A paramedic needs to administer 250 mg of a drug supplied as 500 mg/10 mL. What volume should be administered?
- 2.5 mL
- 5 mL (Correct answer)
- 7.5 mL
- 10 mL
Correct answer: 5 mL
Using the formula: Volume = (Desired dose / Available dose) × Volume on hand = (250/500) × 10 = 5 mL.
Question 4: Which antidysrhythmic is the FIRST-LINE drug for ventricular fibrillation refractory to defibrillation?
- Lidocaine 1.5 mg/kg IV
- Magnesium sulfate 2 g IV
- Amiodarone 300 mg IV bolus (Correct answer)
- Procainamide 20 mg/min IV
Correct answer: Amiodarone 300 mg IV bolus
Current AHA guidelines recommend amiodarone 300 mg IV as first-line antidysrhythmic for shock-refractory VF/pulseless VT.
Question 5: Ondansetron (Zofran) exerts its antiemetic effect by blocking which receptor type?
- Dopamine D2 receptors
- Histamine H1 receptors
- Serotonin 5-HT3 receptors (Correct answer)
- Muscarinic M1 receptors
Correct answer: Serotonin 5-HT3 receptors
Ondansetron selectively antagonizes 5-HT3 serotonin receptors in the GI tract and chemoreceptor trigger zone to prevent nausea and vomiting.
Question 6: A patient with a known allergy to aspirin requires antiplatelet therapy after a STEMI. Which agent is most appropriate?
- Ibuprofen 400 mg PO
- Clopidogrel (Plavix) 300 mg PO (Correct answer)
- Warfarin 5 mg PO
- Heparin 5,000 units IV
Correct answer: Clopidogrel (Plavix) 300 mg PO
Clopidogrel is an ADP receptor antagonist (P2Y12 inhibitor) that provides antiplatelet therapy without the cross-reactivity seen with NSAIDs.
Question 7: Which vasopressor works by releasing norepinephrine from sympathetic nerve terminals rather than directly stimulating adrenergic receptors?
- Epinephrine
- Norepinephrine
- Dopamine
- Ephedrine (Correct answer)
Correct answer: Ephedrine
Ephedrine is an indirect-acting sympathomimetic that displaces norepinephrine from vesicles at sympathetic nerve terminals.
AEMCA Pharmacology for Paramedics 5
A patient on chronic lithium therapy presents with nausea, tremor, and altered mental status.
This presentation is most consistent with: