Insulin NPH

Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product

Suspension, Subcutaneous:

HumuLIN N: 100 units/mL (3 mL, 10 mL) [contains metacresol, phenol]

NovoLIN N: 100 units/mL (10 mL) [contains metacresol, phenol]

NovoLIN N ReliOn: 100 units/mL (10 mL) [contains metacresol, phenol]

Suspension Pen-injector, Subcutaneous:

HumuLIN N KwikPen: 100 units/mL (3 mL) [contains metacresol, phenol]

HumuLIN N Pen: 100 units/mL (3 mL [DSC]) [contains metacresol, phenol]

1-2 hours; Peak effect: 4-12 hours

Time to Peak

Plasma: 6-10 hours

Treatment of type 1 diabetes mellitus (insulin dependent, IDDM) and type 2 diabetes mellitus (noninsulin dependent, NIDDM) to improve glycemic control

Hypersensitivity to insulin NPH or any component of the formulation

No dosage adjustment provided in manufacturer’s labeling; insulin requirements may be reduced due to changes in insulin clearance or metabolism; monitor blood glucose closely.

Refer to indication-specific dosing for obesity-related information (may not be available for all indications).

For SubQ administration:

Humulin® N vials: May be diluted with the universal diluent, Sterile Diluent for Humalog®, Humulin® N, Humulin® R, Humulin® 70/30, and Humulin® R U-500. Do not dilute insulin contained in a cartridge or prefilled pen.

Novolin® N: Insulin Diluting Medium for NovoLog® is not intended for use with Novolin® N or any insulin product other than insulin aspart.

SubQ administration: For subcutaneous administration into the thigh, upper arm, buttocks, or abdomen; do not administer IM or IV, or in an insulin pump. Rotate injection sites within the same region to reduce the risk of lipodystrophy. In order to properly resuspend the insulin, vials should be carefully shaken or rolled several times, prefilled pens should be rolled between the palms ten times and inverted 180° ten times, and cartridges should be inverted 180° at least ten times. Properly resuspended insulin NPH should look uniformly cloudy or milky; do not use if any white insulin substance remains at the bottom of the container, if any clumps are present, or if white particles are stuck to the bottom or wall of the container. Cold injections should be avoided. When mixing insulin NPH with other preparations of insulin (eg, insulin aspart, insulin glulisine, insulin lispro, insulin regular), insulin NPH should be drawn into the syringe after the other insulin preparations. Do not dilute or mix other insulin formulations with insulin NPH contained in a cartridge or prefilled pen.

Concerns related to adverse effects:

• Hypoglycemia: The most common adverse effect of insulin is hypoglycemia. The timing of hypoglycemia differs among various insulin formulations. Hypoglycemia may result from increased work or exercise without eating; use of long-acting insulin preparations (eg, insulin detemir, insulin glargine) may delay recovery from hypoglycemia. Profound and prolonged episodes of hypoglycemia may result in convulsions, unconsciousness, temporary or permanent brain damage or even death. Insulin requirements may be altered during illness, emotional disturbances or other stressors. Instruct patients to use caution with ethanol; may increase risk of hypoglycemia.

• Hypokalemia: Insulin (especially IV insulin) causes a shift of potassium from the extracellular space to the intracellular space, possibly producing hypokalemia. If left untreated, hypokalemia may result in respiratory paralysis, ventricular arrhythmia and even death. Use with caution in patients at risk for hypokalemia (eg, loop diuretic use). Monitor serum potassium and supplement potassium when necessary.

Disease-related concerns:

• Hepatic impairment: Use with caution in patients with hepatic impairment. Dosage requirements may be reduced.

• Renal impairment: Use with caution in patients with renal impairment. Dosage requirements may be reduced.

Concurrent drug therapy issues:

• Drug-drug interactions: Potentially significant interactions may exist, requiring dose or frequency adjustment, additional monitoring, and/or selection of alternative therapy. Consult drug interactions database for more detailed information.

Dosage form specific issues:

• Multiple dose injection pens: According to the Centers for Disease Control and Prevention (CDC), pen-shaped injection devices should never be used for more than one person (even when the needle is changed) because of the risk of infection. The injection device should be clearly labeled with individual patient information to ensure that the correct pen is used (CDC, 2012).

Other warnings/precautions:

• Administration: Insulin NPH is NOT intended for IV or IM administration.

• Appropriate use: Diabetes mellitus: The general objective of exogenous insulin therapy is to approximate the physiologic pattern of insulin secretion which is characterized by two distinct phases. Phase 1 insulin secretion suppresses hepatic glucose production and phase 2 insulin secretion occurs in response to carbohydrate ingestion; therefore, exogenous insulin therapy may consist of basal insulin (eg, intermediate- [insulin NPH] or long-acting insulin or via continuous subcutaneous insulin infusion [CSII]) and/or preprandial insulin (eg, short- or rapid-acting insulin) (see Related Information: Insulin Products). Patients with type 1 diabetes do not produce endogenous insulin; therefore, these patients require both basal and preprandial insulin administration. Patients with type 2 diabetes retain some beta-cell function in the early stages of their disease; however, as the disease progresses, phase 1 insulin secretion may become completely impaired and phase 2 insulin secretion becomes delayed and/or inadequate in response to meals. Therefore, patients with type 2 diabetes may be treated with oral antidiabetic agents, basal insulin, and/or preprandial insulin depending on the stage of disease and current glycemic control. Since treatment regimens often consist of multiple agents, dosage adjustments must address the specific phase of insulin release that is primarily contributing to the patient’s impaired glycemic control. Treatment and monitoring regimens must be individualized.

• Patient education: Diabetes self-management education (DSME) is essential to maximize the effectiveness of therapy.