Phentolamine

Products

Phentolamine was commercially available as a solution for injection in many countries (Regitin, out of trade).

Structure and properties

Phentolamine (C₁₇H₁₉N₃O, M_r = 281.4 g/mol) is present in drugs as phentolamine mesilate, a white, crystalline, slightly hygroscopic powder that is readily soluble in water.

Effects

Phentolamine (ATC C04AB01) is a competitive nonselective alpha₁– and alpha₂–alpha blocker. It is vasodilatory, antihypertensive, positively inotropic, and chronotropic.

Indications

• Blood pressure crises in pheochromocytoma.
• Regitin test in suspected pheochromocytoma.
• Acidental intravenous or paravalvular administration of norepinephrine.