Doxazosin: a newly developed, selective alpha 1-inhibitor in the management of patients with pheochromocytoma.
Although surgical removal is the therapy of choice in patients with pheochromocytoma, medical management is necessary in the preoperative preparation of these patients and in inoperable cases. An alpha-adrenoceptor-blocking agent is routinely used as initial therapy to control hypertension, with a beta-blocker used as a second-step agent to control tachycardia when indicated. Doxazosin, a selective alpha 1-inhibitor used as an antihypertensive agent for the reduction of coronary heart disease risk in hypertensive patients, appears to be a good agent to control blood pressure with minimal changes in heart rate. The aim of this study was to assess the antihypertensive efficacy and safety of doxazosin when used alone or in conjunction with a beta-blocker in 24 patients with pheochromocytoma. Overall excellent or good antihypertensive efficacy was assessed by physicians in 19 of 24 patients (79.2%) enrolled in the study. Doxazosin monotherapy was effective in eight of 12 patients (66.7%), and combined therapy with a beta-blocker was effective in 11 of 12 patients (91.7%). The mean pulse rate remained constant throughout therapy. Adverse reactions were minor and transient and occurred in only three patients. Urinary and plasma catecholamine levels tended to decrease or remained unchanged during doxazosin therapy. There were no clinically hazardous abnormalities or problems in hematologic and biochemical laboratory data. Overall, doxazosin was considered very useful or useful in 83.3% of patients. In conclusion, doxazosin appears to be an excellent agent for the management of hypertension associated with pheochromocytoma.
Miura
Y
Y
Second Department of Internal Medicine, Tohoku University School of Medicine, Sendai, Japan.
Yoshinaga
K
K
D000310:Adrenal Gland Neoplasms / Q000503:physiopathology*; D000317:Adrenergic alpha-Antagonists / Q000009:adverse effects / Q000627:therapeutic use*; D000328:Adult; D000368:Aged; D000959:Antihypertensive Agents / Q000009:adverse effects / Q000627:therapeutic use*; D002395:Catecholamines / Q000378:metabolism; D017292:Doxazosin; D005260:Female; D006801:Humans; D006973:Hypertension / Q000188:drug therapy* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D010673:Pheochromocytoma / Q000503:physiopathology*; D011224:Prazosin / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000627:therapeutic use
D000317:Adrenergic alpha-Antagonists; D000959:Antihypertensive Agents; D002395:Catecholamines; D017292:Doxazosin; D011224:Prazosin