Which of the following correctly pairs a sympathomimetic drug with its primary mechanism of action that is NOT direct receptor stimulation?
- A Phenylephrine — indirectly releases norepinephrine from vesicles
- B Dobutamine — is a prodrug converted to epinephrine intraneuronally
- C Cocaine — blocks neuronal norepinephrine re-uptake transporter (NET) ✓
- D Salbutamol — inhibits catechol-O-methyltransferase to increase NE levels
Correct answer: C. Cocaine — blocks neuronal norepinephrine re-uptake transporter (NET)
Explanation
Cocaine is a prototypical indirect sympathomimetic that blocks the neuronal re-uptake transporter (NET/DAT), potentiating the effects of endogenously released catecholamines. Phenylephrine is a direct alpha-1 agonist; dobutamine is a direct beta-1/beta-2 agonist synthesized to avoid alpha stimulation; salbutamol is a direct beta-2 agonist.
Reference: KD Tripathi, Essentials of Medical Pharmacology, 8th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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