N-Epi Dosage/Direction for Use

Recommended dose: For blood pressure control in acute hypotension.
Adult: Blood volume depletion should always be corrected as fully as possible before any vasopressor is administered.
When, as an emergency measure, intraaortic pressures must be maintained to prevent cerebral or coronary artery ischemia, norepinephrine bitartrate can be administered before and concurrently with blood volume replacement.
Average dosage: Add a 4 ml ampoule (4 mg) of norepinephrine bitartrate to 1000 ml of a 5% dextrose containing solution. Each ml of this dilution contains 4 mcg of the base of norepinephrine bitartrate.
Give this solution by IV infusion. Insert a plastic IV catheter through a suitable bore needle well advanced centrally into the vein and securely fixed with adhesive tape.
An IV drip chamber or other suitable metering device is essential to permit an accurate estimation of the rate of flow in drops per minute. After observing the response to an initial dose of 2 ml to 3 ml (from 8 mcg to 12 mcg of base) per minute, adjust the rate of flow to establish and maintain a low normal blood pressure (usually 80 mmHg to 100 mmHg systolic) sufficient to maintain the circulation to vital organs.
In previously hypertensive patients, it is recommended that the blood pressure should be raised no more than 40 mmHg below the preexisting systolic pressure. The average maintenance dose ranges from 0.5 ml to 1 ml per min (from 2 mcg to 4 mcg of base).
High dosage: Great individual variation occurs in the dose required to attain and maintain an adequate blood pressure. In all cases, dosage of norepinephrine bitartrate should be titrated according to the response of the patient. Occasionally much larger or even enormous daily doses (as high as 68 mg base or 17 ampoules) may be necessary if the patient remains hypotensive, but occult blood volume depletion should always be suspected and corrected when present. Central venous pressure monitoring is usually helpful in detecting and treating this situation.
Fluid intake: The degree of dilution depends on clinical fluid volume requirements. If large volumes of fluid (dextrose) are needed at a flow rate that would involve an excessive dose of the pressor agent per unit of time, a solution more dilute than 4 mcg per ml should be used. On the other hand, when large volumes of fluid are clinically undesirable, a concentration more than 4 mcg/ml may be necessary.
Duration of therapy: The infusion should be continued until adequate blood pressure and tissue perfusion are maintained without therapy. Infusions of norepinephrine bitartrate should be reduced gradually, avoiding abrupt withdrawal.
In some of the reported cases of vascular collapse due to acute Ml, treatment was required for up to 6 days.
Children: Not recommended. Safety and efficacy of norepinephrine in pediatric patients have not been established.
Elderly: See adult dosage. Norepinephrine infusions should not be administered into the veins of the legs in elderly patients.
Patients with hepatic impairment: No specific recommendations are available.
Patients with renal impairment: No specific recommendations are available.
Maximum dose: Adults: 30 mcg/min IV continuous infusion.
Elderly: 30 mcg/min IV continuous infusion.
Adolescents: 30 mcg/min IV continuous infusion.
Mode of administration: Norepinephrine bitartrate is a concentrated, potent drug which must be diluted in dextrose containing solutions prior to infusion, an infusion of norepinephrine bitartrate should be given into a large vein. The Injection is not to be used if its colour is pinkish or darker than slightly yellow or if it contains a precipitate.