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Phentolamine

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Phentolamine, Rogatine

  • See Also
  1. Alpha Adrenergic Receptor Blocker
  2. Phenoxybenzamine
  3. Hypertensive Crisis
  4. Pheochromocytoma
  5. Vasopressor Extravasation
  • Indications
  1. Hypertensive Crisis in Pheochromocytoma
  2. Vasopressor Extravasation ( IV Extravasation of Catecholamines)
  • Dosing
  • Adults
  1. Hypertensive Crisis in Pheochromocytoma
    1. Give 5 mg IV/IM for one dose
    2. Results in profound Blood Pressure drop (e.g. 60/25 mmHg decrease in BP)
  2. Vasopressor Extravasation (e.g. Norepinephrine) - Not FDA approved
    1. Prepare 5-10 mg in 10 ml Normal Saline
    2. Inject 1 ml SC around extravasation site within 12 hours of extravasation
    3. In adults may repeat dose up to a total of 5 ml injected around extravasation site
  • Dosing
  • Children
  1. Hypertensive Crisis in Pheochromocytoma
    1. Give 0.05 to 0.1 mg/kg (up to 5 mg) IV/IM for one dose
    2. Results in profound Blood Pressure drop (e.g. 60/25 mmHg decrease in BP)
  2. Vasopressor Extravasation (e.g. Norepinephrine) - Not FDA approved
    1. Prepare 5 mg in 10 ml Normal Saline
    2. Inject 1 ml SC around extravasation site within 12 hours of extravasation
  • Mechanism
  1. Synthetic imidazoline acts as a competitive Alpha Adrenergic Antagonist at alpha-1 and alpha-2 receptors resulting in vasodilation
  2. May block 5-HT receptors
  3. May stimulate Histamine release from Mast Cells
  • Adverse Effects
  1. Hypotension
  2. Generalized Weakness
  • Safety
  1. Pregnancy Category C
  2. Unknown Safety in Lactation
  • Resources
  1. Phentolamine (DailyMed)
    1. https://dailymed.nlm.nih.gov/dailymed/lookup.cfm?setid=fe1e10f5-4ff3-4616-9534-489648d88d33