Classes
DEA Class; Rx
Common Brand Names; Regitine, OraVerse
- Alpha Blockers, Antihypertensives;
- Extravasation Antidotes
Description
Has positive inotropic and chronotropic effect on the heart
Blocks alph-adrenergic receptors to briefly antagonize circulating epinephrine and norepinephrine to reduce hypertension caused by alpha effects of the endogenous catecholamines
Indications
Indicated For the treatment of Pheochromocytoma
Treatment of hypertension during pheochromocytoma surgery
Epinephrine or norepinephrine extravastation treatment
Indicated for reversal of soft-tissue anesthesia associated with functional deficits from intraoral local anesthesia containing a vasoconstrictor
Contraindications
Hypersensitivity; MI or other CAD
Adverse Effects
- Nasal congestion (10% )
- Post-treatment pain (up to 10% )
- Injection site pain (4% to 6% )
- Diarrhea (<3% )
- Cardiac dysrhythmia
- Chest pain
- Hypotension
- Myocardial infarction
- CVA – cerebrovascular accident due to cerebral artery occlusion
Warnings
First dose effect may occur, causing a sudden and drastic fall in blood pressure after administering the first dose.
Hypotension/syncope with first few doses or with increase in dose; minimize by using small first dose at bedtime
Increase dose slowly
Myocardial infarction, cerebrovascular spasm, and cerebrovascular occlusion reported following parenteral administration of phentolamine; these events usually occurred in association with marked hypotensive episodes producing shock-like states
Tachycardia and cardiac arrhythmias may occur with use of phentolamine or other alpha-adrenergic blocking agents; although such effects are uncommon after administration, clinicians should be alert to signs and symptoms of these events, particularly in patients with a prior history of cardiovascular disease; discontinue if angina occur or worsen
Pregnancy and Lactation
Pregnancy Category: C
Lactation: not known if excreted in breast milk; not recommended
Maximum Dosage
Adults
Pheochromocytoma
Diagnosis: 5 mg IV/IM
Test for pheochromocytoma is positive if decrease SBP >35 mmHg & decrease DBP >25 mmHg
Pheochromocytoma Surgery Use
5 mg IV/IM 1-2 hr preoperative, repeat if necessary q2-4hr
Extravasation Treatment
Epinephrine or norepinephrine extravastation treatment
Treatment: 5-10 mg in 10 mL NS local injection within 12 hr
Prevention: 10 mg for each liter of IV fluids (pressor effect of NE is unaffected)
Dental Anesthesia Reversal (OraVerse)
Administer using same locations and techniques (infiltration or block injection) as local anesthetic
1/2 cartridge local anesthetic: OraVerse 1/2 cartridge (0.2 mg)
1 cartridge local anesthetic: OraVerse 1 cartridge (0.4 mg)
2 cartridges local anesthetic: OraVerse 2 cartridges (0.8 mg)
Hypertensive Crises (Off-label)
Secondary to catecholamine excess: 5-15 mg IV
Pediatric
Pheochromocytoma, Diagnosis
0.1-0.2 mg/kg IV/IM, OR 1 mg IV OR 3 mg IM
Pheochromocytoma Surgery Use
Treatment of hypertension during surgery
0.05-0.1 mg/kg/dose OR 1 mg IV/IM 1-2 hr preoperative, repeat q2-4hr until hypertension is controlled; not to exceed 5 mg/dose
Dental Anesthesia Reversal (OraVerse)
<6 years or <15 kg: Safety and efficacy not established
Dose based on amount of local anesthetic administered
6-12 years (15-30 kg)
For 1/2 cartridge local anesthetic, use OraVerse 1/2 cartridge (0.2 mg)
6-12 years (>30 kg)
1/2 cartridge local anesthetic: OraVerse 1/2 cartridge (0.2 mg)
1 cartridge local anesthetic: OraVerse 1 cartridge (0.4 mg)
Other Information
Extravasation of epinephrine/norepinephrine:0.1-0.2 mg/kg to no more than 10 mg
How supplied
Phentolamine mesylate
powder for injection
- 5mg
injectable solution
- 0.4mg/1.7mL
