A patient with pheochromocytoma crisis is being prepared for surgery. The sequence of drug administration should be:
- A Beta-blocker first for 2 weeks, then alpha-blocker in the final week before surgery
- B Alpha-blocker (phenoxybenzamine) first for 10–14 days, then beta-blocker added only if tachycardia persists ✓
- C Simultaneous alpha and beta blockade begun together 3 days pre-operatively
- D Calcium channel blocker alone is sufficient; adrenergic blockade is not required
Correct answer: B. Alpha-blocker (phenoxybenzamine) first for 10–14 days, then beta-blocker added only if tachycardia persists
Explanation
Alpha-blockade must be established first (phenoxybenzamine for 10–14 days) to prevent unopposed alpha-mediated vasoconstriction. If a beta-blocker is given first, the loss of beta-2-mediated vasodilation plus retained alpha-mediated vasoconstriction can precipitate a hypertensive crisis. Beta-blockers are added only after alpha-blockade is established and only for tachycardia control.
Reference: KD Tripathi, Essentials of Medical Pharmacology, 8th ed.
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Written and medically reviewed by the StethoPrep medical team.