Phentolamine

1. INDICATONS AND USAGE OraVerse an alpha adrenergic blocker, is indicated for adult and pediatric patients ages 3 years and older for the reversal of soft-tissue anesthesia, i.e., anesthesia of the lip and tongue, and the associated functional deficits resulting from an intraoral submucosal injection of a local anesthetic containing a vasoconstrictor. OraVerse, an alpha adrenergic blocker, is indicated for adult and pediatric patients ages 3 years and older for the reversal of soft-tissue anesthesia, i.e., anesthesia of the lip and tongue, and the associated functional deficits resulting from an intraoral submucosal injection of a local anesthetic containing a vasoconstrictor.

The mechanism by which OraVerse accelerates reversal of soft-tissue anesthesia and the associated functional deficits is not fully understood. Phentolamine mesylate, the active ingredient in OraVerse, produces an alpha-adrenergic block of relatively short duration resulting in vasodilatation when applied to vascular smooth muscle. In an animal model, OraVerse increased local blood flow in submucosal tissue of the dog when given after an intraoral injection of lidocaine 2% with 1:100,000 epinephrine.

2. DOSAGE AND ADMINISTRATION Amount of Local Anesthetic Administered Dose of OraVerse 1 / 4 Cartridge 1 / 4 Cartridge (0.1 mg) ½ Cartridge ½ Cartridge (0.2 mg) 1 Cartridge 1 Cartridge (0.4 mg) 2 Cartridges 2 Cartridges (0.8 mg) OraVerse is administered using the same location(s) and same technique(s) (infiltration or block injection) used for the administration of local anesthetic.

4. CONTRAINDICATIONS OraVerse is contraindicated in patients with: Hypersensitivity to the active substance or to any ingredients in the formulation OraVerse is contraindicated in patients with: Hypersensitivity to the active substance or to any ingredients in the formulation.

5. WARNINGS AND PRECAUTIONS Myocardial infarction, cerebrovascular spasm, and cerebrovascular occlusion have been reported to occur following the intravenous or intramuscular administration of phentolamine, usually in association with marked hypotensive episodes or shock-like states which occasionally follow parenteral administration. Tachycardia and cardiac arrhythmiasmay occur with the use of phentolamine or other alpha-adrenergic blocking agents.

6. ADVERSE REACTIONS In clinical trials, the most common adverse reaction with OraVerse that was greater than the control group was injection site pain. The most common adverse reaction with OraVerse (incidence ≥5% and > control) is injection-site pain.

7. DRUG INTERACTIONS There are no known drug interactions with OraVerse. Lidocaine and Epinephrine When OraVerse was administered as an intraoral submucosal injection 30 minutes after injection of a local anesthetic, 2% lidocaine HCl with 1:100,000 epinephrine, the lidocaine concentration increased immediately after OraVerse intraoral injection. Lidocaine AUC and Cmax values were not affected by administration of OraVerse. OraVerse administration did not affect the PK of epinephrine.

Store at controlled room temperature, 20-25°C (68-77°F) with brief excursions permitted between 15-30°C (59-86°F) Protect from direct heat and light. Do not permit to freeze.