Abrupt withdrawal of the antihypertensive agent tiamenidine after 12-months' treatment

Ten patients were treated with tiamenidine, an antihypertensive agent which is chemically related to clonidine, for 12 months. The drug was then abruptly stopped and observations made of blood pressure, plasma renins and urinary metanephrines. Transient withdrawal systolic hypertension occurred in 1 patient, and although plasma renins rose there was no consistent evidence of excess catecholamine activity during the post-treatment period.