5.1 Tissue Ischemia
Administration of LEVOPHED to patients who are hypotensive from hypovolemia can result in severe peripheral and visceral vasoconstriction, decreased renal perfusion and reduced urine output, tissue hypoxia, lactic acidosis, and reduced systemic blood flow despite "normal" blood pressure. Address hypovolemia prior to initiating LEVOPHED [see Dosage and Administration (2.1)]. Avoid LEVOPHED in patients with mesenteric or peripheral vascular thrombosis, as this may increase ischemia and extend the area of infarction.
Gangrene of the extremities has occurred in patients with occlusive or thrombotic vascular disease or who received prolonged or high dose infusions. Monitor for changes to the skin of the extremities in susceptible patients.
Extravasation of LEVOPHED may cause necrosis and sloughing of surrounding tissue. To reduce the risk of extravasation, infuse into a large vein, check the infusion site frequently for free flow, and monitor for signs of extravasation [see Dosage and Administration (2.1)].
Emergency Treatment of Extravasation
To prevent sloughing and necrosis in areas in which extravasation has occurred, infiltrate the ischemic area as soon as possible, using a syringe with a fine hypodermic needle with 5 to 10 mg of phentolamine mesylate in 10 to 15 mL of 0.9% Sodium Chloride Injection in adults.
Sympathetic blockade with phentolamine causes immediate and conspicuous local hyperemic changes if the area is infiltrated within 12 hours.
5.2 Hypotension after Abrupt Discontinuation
Sudden cessation of the infusion rate may result in marked hypotension. When discontinuing the infusion, gradually reduce the LEVOPHED infusion rate while expanding blood volume with intravenous fluids.
5.3 Cardiac Arrhythmias
LEVOPHED elevates intracellular calcium concentrations and may cause arrhythmias, particularly in the setting of hypoxia or hypercarbia. Perform continuous cardiac monitoring of patients with arrhythmias.
5.4 Allergic Reactions Associated with Sulfite
LEVOPHED contains sodium metabisulfite, a sulfite that may cause allergic-type reactions including anaphylactic symptoms and life-threatening or less severe asthmatic episodes in certain susceptible people. The overall prevalence of sulfite sensitivity in the general population is unknown. Sulfite sensitivity is seen more frequently in asthmatic than in non-asthmatic people.