Phentolamine

Phentolamine is a reversible, non-selective alpha-adrenergic blocker that induces vasodilation. While initially introduced to the market for the treatment of hypertension, this clinical use was halted due to cardiovascular and gastrointestinal adverse effects with the prolonged use of large oral doses of phentolamine. It has several therapeutic uses, including the treatment of hypertensive episodes, prevention of norepinephrine-induced extravasation, diagnosis of pheochromocytoma, reversal of soft-tissue anesthesia, and treatment of pharmacologically-induced mydriasis. Phentolamine is administered intravenously, intramuscularly, submucosally, and topically.

1.用于预防和治疗嗜铬细胞瘤所致的高血压发作，包括手术切除时出现的阵发性高血压，也可根据血压对本品的反应用于协助诊断嗜铬细胞瘤；

2.治疗左心衰竭；

3.治疗去甲肾上腺素、去氧肾上腺素、间羟胺等静脉给药外溢，用于防止皮肤坏死；

4.临床还用于治疗男性勃起功能障碍（ED）。最新研究表明，本品与罂粟碱、前列地尔三联用药，可降低引起平滑肌收缩的交感神经张力，使阴茎动脉平滑肌松弛，增加阴茎动脉血流，有利勃起。