Phentolamine hydrochloride is A nonselective alpha-adrenergic antagonist. It is used in ... hypertension and Name: Phentolamine mesilate, Phentolamine mesylate, Phentolamine hcl, Phentolamine hydrochloride, Phentolamine.A nonselective alpha-adrenergic antagonist. It is used in ... frostbite, clonidine withdrawal syndrome, impotence, and peripheral vascular disease Phentolamine hydrochloride