1. at receptor antagonists u 1.3 Adverse effects a(1)Postural hypotension u(2) Reflex heart stimulation u tachycardia, arrhythmia, angina pectoris u 3)GI reactions u(4)Other central depression1.3 Adverse effects (1) Postural hypotension (2) Reflex heart stimulation tachycardia, arrhythmia, angina pectoris (3) G.I. reactions (4) Other central depression 1.  receptor antagonists