In rare instances, SBP may be low: a) check for etiology (volemia, sepsis, etc.); b) use low dose noradrenaline rather than tapering alpha-2 agonists; c) a second best practice is to lower the dose or suppress alpha-2 agonist administration and carry on with neuroleptics, scaled up to absence of agitation, hallucination, tremor. Basically, there is no maximal dose for neuroleptics: the patient should be quiet without tremor without resorting to general anesthesia or high dose benzodiazepine (ventilatory side-effects). This evidence concerns the gene PSMA2 and Tremor.