“…87 Phentermine is an amphetamine derivative used as an appetite suppressant, which is thought to be a sympathomimetic amines that stimulate the release of norepinephrine and dopamine from the storage sites in the presynaptic nerve terminals. 119 Other catecholamine-related causes included indirect adrenergic effects, including parasympathetic block (2 cases), 117,122 sudden withdrawal of b-blockers (3 cases), 76,77 anaphylactic reactions (5 cases), [81][82][83][84]118 withdrawal of opioids (5 cases), 69,70,75,78,79 or alcohol (2 cases). 71,125 Opioid withdrawal is known to cause hyperadrenergic state that leads to catecholamine surge and increased b-receptor sensitivity and subsequently myocardial stunning.…”