Avoid Hypertension: Because of the potency and varying responses to Levophed SF, the possibility exists that hypertension may be produced with overdoses of this pressor agent. Hence, it is desirable to record the blood pressure every 2 min from the time administration is started until the desired blood pressure is obtained, and then every 5 min if administration is to be continued. The rate of flow must be watched constantly and the patient should never be left unattended while receiving norepinephrine. Headache may be a symptom of hypertension due to overdosage.
Hypersensitivity: Certain patients may be hypersensitive to the effects of Levophed SF eg, hyperthyroidism patients (see Adverse Reactions).
Site of Infusion: Levophed SF should be given into a large vein, particularly an antecubital vein, because when administered into this vein, the risk of necrosis of the overlying skin from prolonged vasoconstriction is apparently very slight. The femoral vein is also an acceptable route of administration. A catheter tie-in technique should be avoided, if possible, since the obstruction to blood flow around the tubing may cause stasis and increased local concentration of Levophed SF. As occlusive vascular diseases (eg, atherosclerosis, arteriosclerosis, diabetic endarteritis, Buerger's disease) are more likely to occur in the lower rather than in the upper extremity, the leg veins in elderly patients or in those suffering from such disorders should be avoided. Gangrene has been reported in lower extremity when infusions of Levophed were given in an ankle vein.
Extravasation: The infusion site should be checked frequently for free flow. Care should be taken to avoid extravasation of norepinephrine into the tissues, as local necrosis might ensue due to the vasoconstrictive action of Levophed SF. Blanching along the course of the infused vein, sometimes without obvious extravasation, has been attributed to vasa vasorum constriction with increased permeability of the vein wall, permitting some leakage.
This may also progress on rare occasions to superficial slough, particularly during infusion into leg veins in elderly patients or in those suffering from obliterative vascular disease. Hence, if blanching occurs, consideration should be given to changing the infusion site at intervals to allow the effects of local vasoconstriction to subside.
Antidote for Extravasation Ischemia: To prevent sloughing and necrosis in areas in which extravasation has occurred, the area should be infiltrated as soon as possible with 10-15 mL of saline solution containing 5-10 mg of phentolamine, an adrenergic-blocking agent. Using a syringe with a fine hypodermic needle, the solution is infiltrated liberally throughout the area, which is easily identified by its cold, hard and pallid appearance. Sympathetic blockade with phentolamine causes immediate and conspicuous local hyperemic changes if the area is infiltrated within 12 hrs. Therefore, phentolamine should be given as soon as possible after the extravasation is noted.
Carcinogenicity, Mutagenicity & Impairment of Fertility: Studies have not been performed.
Use in pregnancy: Animal reproduction studies have not been conducted with norepinephrine. It is also not known whether norepinephrine can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. Norepinephrine should be given to a pregnant woman only if clearly needed.
Use in lactation: It is not known whether Levophed SF is excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when norepinephrine is administered to a nursing woman.
Use in children: Safety and effectiveness in children have not been established.
Use in the elderly: Clinical studies of norepinephrine did not include sufficient numbers of subjects ≥65 years to determine whether they respond differently from younger subjects. Although clinical experience has not identified, differences in responses between the elderly and younger patients, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal or cardiac function, and of concomitant disease or other therapy.
Norepinephrine infusions should not be administered into the veins in the leg in elderly patients.