A 29-year-old man with generalized anxiety disorder started on propranolol 80 mg daily presents with improved palpitations and tremor. However, he continues experiencing excessive diaphoresis and sense of impending doom. Vital signs show BP 118/76 mmHg, HR 68 bpm, RR 16/min, temperature 37°C. Recent labs reveal normal TSH and cortisol levels. He denies polyuria or polydipsia. Which mechanism best explains why propranolol failed to relieve his anxiety and diaphoresis?
- A)Propranolol blocks muscarinic receptors preventing parasympathetic compensation
- B)Propranolol blocks only β-adrenergic peripheral manifestations, not central anxiety mediated by neurotransmittersGABARITO
- C)Propranolol increases GABA reuptake, worsening anxiety
- D)Propranolol inhibits α1-adrenergic receptors causing reflex tachycardia
- E)Propranolol enhances serotonin metabolism in the amygdala
Explicação
Propranolol is a β-blocker that addresses the somatic (peripheral) manifestations of anxiety such as palpitations, tremor, and tachycardia by blocking β1 effects on the heart and β2 effects on skeletal muscle. However, it does not treat the cognitive and emoti... Ver explicação completa e trilha adaptativa →