Effects of Clonidine Withdrawal: Possible Mechanisms and Suggestions for Management

A severe rebound rise in blood pressure with agitation and insomnia had been noted in five patients when they had previously ceased clonidine (Catapres) This has been shown to be reproducible in these patients and to be associated with a significant increase in urinary catecholamine excretion. The blood pressure can be controlled and the symptoms alleviated promptly by alpha and beta adrenergic receptor blockade using intravenous phentolamine and propranolol.