phentolamine

Phentolamine is a reversible, non-selective alpha-adrenergic antagonist (alpha blocker) that induces vasodilation by competitively blocking both alpha-1 and alpha-2 adrenergic receptors. It is primarily used for the prevention or control of hypertensive episodes in patients with pheochromocytoma, for the diagnosis of pheochromocytoma via the phentolamine blocking test, and to prevent or treat dermal necrosis following norepinephrine extravasation. Phentolamine can also be used to reverse soft tissue anesthesia and pharmacologically induced mydriasis. Additionally, it has been used as an intracavernosal injection to induce erections by increasing penile blood flow through smooth muscle relaxation. Its mechanism involves direct antagonism at alpha-1 and alpha-2 adrenergic receptors on vascular smooth muscle as well as indirect endothelium-mediated mechanisms involving nitric oxide synthase activation[1][3][6][8].

Brand names

RegitineOraVerseRyzumvi

Other names

phentolamine mesylate