Terazosin as First Line Preoperative Blockade in Filipino Patients Diagnosed with Pheochromocytoma

Preoperative blockade in controlling hypertension in patients with pheochromocytoma is essential to improve intraoperative hemodynamic stability and minimize morbidity during resection of the adrenal mass. Phenoxybenzamine, a non-selective alpha adrenergic blocker, has been widely used in blood pressure control for this condition, but is unavailable in the Philippines. Selective alpha-1 antagonists have been used in lieu of phenoxybenzamine and are beneficial in reducing the adverse effects experienced by patients on phenoxybenzamine. Several case reports have documented using doxazosin and prazosin, both selective alpha-1 antagonists, as preoperative blockade. Terazosin is widely available to treat benign prostatic hypertrophy and has the same pharmacokinetic characteristics as doxazosin but with a shorter half life. There is little experience with the use of the drug to control BP in pheochromocytoma. In this case series, we gave terazosin up to a maximum of 4 mg/day as preoperative blockade in four patients with pheochromocytoma. Terazosin may be safely given to Filipino patients diagnosed with pheochromocytoma as first line preoperative blockade.