Metirosine is an antihypertensive drug. Metyrosine inhibits tyrosine hydroxylase, which catalyzes the first transformation in catecholamine biosynthesis, i.e., the conversion of tyrosine to dihydroxyphenylalanine (DOPA). Because the first step is also the rate-limiting step, blockade of tyrosine hydroxylase activity results in decreased endogenous levels of catecholamines and their synthesis. This consequently, depletes the levels of the catecholamines dopamine, adrenaline and noradrenaline in the body,usually measured as decreased urinary excretion of catecholamines and their metabolites. One main end result of the catecholamine depletion is a decrease in blood presure. Metirosine is used for the treatment of patients with pheochromocytoma, for preoperative preparation of patients for surgery, management of patients when surgery is contraindicated, and chronic treatment of patients with malignant pheochromocytoma.

Racemetirosine is an orally active inhibitor of the enzyme tyrosine 3-monooxygenase, and consequently of the synthesis of catecholamine. At dosages of 600 to 3500mg daily, it is effective in controlling the hypertensive episodes and symptoms of catecholamine excess in phaeochromocytoma during preparation for surgery. Oral Racemetirosine is well absorbed and absorption appears constant in each individual over a wide dosage range. The drug is largely excreted via the kidneys, but extrarenal elimination has not been studied. Case reports on the clinical use of Racemetirosine in phaeochromocytoma indicate that the drug controls hypertension and symptoms of catecholamine excess in most patients during preparation for surgical removal of a tumor. In some cases, the addition of Racemetirosine to phenoxybenzamine plus propranolol has resulted in adequate control of symptoms previously unresponsive to the adrenergic blocking regimen. Drowsiness and sedation have been the most frequently reported side effects of Racemetirosine treatment.

Metirosine is an antihypertensive drug. Metyrosine inhibits tyrosine hydroxylase, which catalyzes the first transformation in catecholamine biosynthesis, i.e., the conversion of tyrosine to dihydroxyphenylalanine (DOPA). Because the first step is also the rate-limiting step, blockade of tyrosine hydroxylase activity results in decreased endogenous levels of catecholamines and their synthesis. This consequently, depletes the levels of the catecholamines dopamine, adrenaline and noradrenaline in the body,usually measured as decreased urinary excretion of catecholamines and their metabolites. One main end result of the catecholamine depletion is a decrease in blood presure. Metirosine is used for the treatment of patients with pheochromocytoma, for preoperative preparation of patients for surgery, management of patients when surgery is contraindicated, and chronic treatment of patients with malignant pheochromocytoma.

Racemetirosine is an orally active inhibitor of the enzyme tyrosine 3-monooxygenase, and consequently of the synthesis of catecholamine. At dosages of 600 to 3500mg daily, it is effective in controlling the hypertensive episodes and symptoms of catecholamine excess in phaeochromocytoma during preparation for surgery. Oral Racemetirosine is well absorbed and absorption appears constant in each individual over a wide dosage range. The drug is largely excreted via the kidneys, but extrarenal elimination has not been studied. Case reports on the clinical use of Racemetirosine in phaeochromocytoma indicate that the drug controls hypertension and symptoms of catecholamine excess in most patients during preparation for surgical removal of a tumor. In some cases, the addition of Racemetirosine to phenoxybenzamine plus propranolol has resulted in adequate control of symptoms previously unresponsive to the adrenergic blocking regimen. Drowsiness and sedation have been the most frequently reported side effects of Racemetirosine treatment.