Ephedrine differs from adrenaline (epinephrine) in all of the following respects EXCEPT:
- A Ephedrine acts both directly and indirectly on adrenergic receptors
- B Ephedrine is effective orally
- C Both drugs stimulate alpha and beta adrenergic receptors ✓
- D Ephedrine does not cross the blood-brain barrier
Correct answer: C. Both drugs stimulate alpha and beta adrenergic receptors
Explanation
Both ephedrine and adrenaline stimulate alpha-1, alpha-2, beta-1, and beta-2 adrenergic receptors, making option C the correct 'EXCEPT' answer — it is a similarity, not a difference. Ephedrine differs from adrenaline in being effective orally (adrenaline is destroyed by gut enzymes), having a mixed direct+indirect mechanism (it also releases norepinephrine from terminals), and readily crossing the blood-brain barrier to produce CNS stimulation.
Reference: KD Tripathi, Essentials of Medical Pharmacology, 8th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.