contraindications any adrenergic stimulation, will cause a hypertensive crisis. e.g. a1 stimulation in a decongestant. this is becasue of the NA elevation. and amphetamines. avoid with general and local anasthesia as it can cause changes in blood pressure like pethidine. serotonergic agents: even St, johns wart and tryptophan, serotonin syndrome: migraines, myoclonus, hyperreflexia, agitation and confusion, to hyperthermia, diaphoresis seizures, coma, cardiovascular collapse, permanent hyperthermic brain damage, and death