Cyclosporin-induced hypertension: incidence, pathogenesis and management.

Blood pressure increases soon after administration of immunosuppressive regimens using cyclosporin. Characteristic vascular changes lead to systemic and renal vasoconstriction. Changes in blood pressure are commonly associated with disturbed circadian regulation and may promote the rapid development of target organ injury, including intracranial haemorrhage, left ventricular hypertrophy and microangiopathic haemolysis. The mechanisms underlying this disorder are complex and include altered vascular endothelial function. Vasodilators such as prostacyclin and nitric oxide are suppressed, whereas vasoconstrictors, including endothelin, are increased. Changes in the kidney include vasoconstriction, reduced glomerular filtration and sodium retention. Effective therapy depends upon rigorous blood pressure control by administration of vasodilating agents, with attention to potential interactions with cyclosporin.