Phentolamine
| Drug | Phentolamine |
| Brand names | Oraverse ®, Rogitine ® |
| Indications | Hypertensive crisis. |
| Mechanism of action | Phentolamine is a non-selective alpha-adrenergic blocker. Phentolamine reduces blood pressure while increasing catecholamine activity. |
| Effects | Primarily causes afterload reduction. |
| Time to onset of action | 1 to 2 minutes |
| Duration of action | 10 to 30 minutes |
| Delivery | IV |
| Dose | Bolus injection: 5 to 15 mg every 5 to 15 minutes as necessary. Continuous infusion: Start infusion at 0.1 mg/min and increase in increments of 0.1 mg. |
| Adverse effects | Tachycardia. Flushing. Headache. Nausea. Vomiting. |
| Caution | Rarely used unless patient has a confirmed diagnosis of pheochromocytoma Treatment of hypertension associated with pheochromocytoma; treatment of dermal necrosis after extravasation of drugs with á-adrenergic effects. |