[Withdrawal effects following interruption of antihypertensive drugs. II. Coronary rebound phenomenon with antihypertensive drugs used in coronary heart disease therapy (author's transl)].

Treatment of hypertension is still primarily relevant of drug therapy. Prolonged use of antihypertensive agents is undoubtedly efficient but may induce when discontinued occasionally or intentionally a true rebound phenomenon i.e. exacerbation or aggravation of the pretreatment morbid condition. Hypertensive rebound occurs almost exclusively after clonidine withdrawal, usually abrupt but sometimes gradual. It consists of an acute clinical syndrome together with well defined biological findings, related to reactional enhanced sympathetic activity and necessitating an emergency treatment. A different rebound phenomenon is observed on withdrawal of some antihypertensive drugs when used in the management of coronary heart disease, namely beta adrenergic receptors blockers and specially propranolol. An acute exacerbation of coronary symptoms with or without severe arrythmias and eventually sudden deaths have been reported. The mechanisms responsible of this event are described, mainly the modifications recently observed at the level of the adrenoreceptors themselves. These two rebound phenomena although rare should be considered seriously by the practitioner while prescribing antihypertensive or antiangorous drugs otherwise very efficient but alble to induce catastrophic symptoms when interrupted in certain circumstancy.