H2 Blockers · Pharmacology

In the management of an acute allergic reaction (anaphylaxis), H2 blockers are sometimes used as adjunctive therapy because:

  1. They directly cause bronchodilation
  2. They block H2 receptors on skin blood vessels
  3. They stabilize the heart rate directly
  4. They slow the hepatic metabolism of epinephrine
Show answer and explanation

Correct answer: They block H2 receptors on skin blood vessels

In addition to H1 receptors, H2 receptors are involved in histamine-mediated vasodilation. Combining an H1 blocker (like diphenhydramine) with an H2 blocker (like famotidine) can be more effective for skin symptoms like hives.

Difficulty: Medium Question 17 of 20

Practice all 20 H2 Blockers questions

Keep practicing

More H2 Blockers questions