Resistant hypertension in the elderly-second line treatments: aldosterone antagonists, central alpha-agonist agents, alpha-adrenergic receptor blockers, direct vasodilators, and exogenous nitric oxide donors.

Resistant hypertension (RH) is a prevalent medical problem across all ages but is more frequent in elderly patients. This entity has to be distinguished from clinical settings which may simulate it such as apparent hypertension (pseudohypertension) or apparently resistant hypertension (pseudoresistant hypertension) [1]. An appropriate therapy for RH can be achieved by the addition of second line antihypertensive drugs: antialdosteronic diuretics, central agents, alpha blockers, direct vasodilating agents, and exogenous nitric oxide donors. These antihypertensive drugs are considered as second line drugs since they are less effective as monotherapy to reduce blood pressure (they induce counte regulatory responses that limit their antihypertensive effect such as volume expansion or reflex tachycardia) and prevent cardiovascular events, or due to significant adverse effects (postural hypotension, sedation, hyperkalemia). Second line drugs are also used when there is allergy or intolerance to the first line ones [2, 3].