What Is Humulin N? Uses, Dosage, and What You Need to Know in 2026

Humulin N is one of the most widely used insulin products in the United States. Whether you've just been prescribed it or are looking to better understand your existing medication, this comprehensive guide covers everything patients need to know about Humulin N in 2026.

What Is Humulin N?

Humulin N is a brand-name insulin made by Eli Lilly and Company. It was first approved by the FDA in 1982. Its generic name is insulin isophane human, also known as NPH insulin (Neutral Protamine Hagedorn — named after its inventor, Hans Christian Hagedorn, and protamine sulfate, which slows its absorption).

Humulin N is classified as an intermediate-acting human insulin. This means it works more slowly than rapid-acting or short-acting insulins but lasts longer. It is primarily used as a basal (background) insulin to control blood sugar levels throughout the day and night, rather than to manage blood sugar spikes around meals.

What Is Humulin N Used For?

Humulin N is FDA-approved for:

Type 1 diabetes: Used as basal insulin, often in combination with a rapid-acting insulin at mealtimes (basal-bolus regimen)

Type 2 diabetes: Used when oral medications or non-insulin injectables are insufficient to control blood sugar

Gestational diabetes: May be used in pregnancy under close medical supervision to control blood sugar

Humulin N is appropriate for adults and pediatric patients. It may be used alone or in combination with a prandial (meal-time) insulin.

What Are the Available Forms and Strengths?

Humulin N comes in one concentration: 100 units per milliliter (U-100). It is available in two forms:

10 mL multi-dose vial: You draw the dose yourself with a syringe. Contains 1,000 units total.

Humulin N KwikPen (3 mL prefilled pen): A disposable prefilled insulin pen that dials in 1-unit increments. More convenient for on-the-go use.

Humulin N is also available over the counter in most U.S. states — you can request it from the pharmacist without a prescription.

What Is the Typical Humulin N Dosage?

Humulin N dosing is highly individualized. Your doctor will calculate your dose based on your weight, blood sugar levels, activity level, and other medications. General guidelines:

Type 1 diabetes (adults): Total daily insulin typically 0.4-1 unit/kg/day; Humulin N may provide approximately 50% of total daily dose as basal insulin

Type 2 diabetes (starting dose): Often 0.1-0.2 units/kg/day, titrated up over time

Children: 0.7-1 unit/kg/day total insulin for Type 1; Humulin N typically 30-45% of total daily dose

Humulin N is typically injected once or twice daily. Your doctor will advise on timing.

How Do You Take Humulin N?

Humulin N is injected subcutaneously (under the skin) only. Do NOT inject into a vein or use in an insulin pump. Key injection tips:

Always mix first: Roll the vial gently 10 times, then tip it up and down 10 times. The liquid should look uniformly white and cloudy — not clear.

Injection sites: Abdomen, thigh, upper arm, or buttocks. Rotate sites within the same region.

Never share: Never share a pen or syringe with another person, even with a fresh needle.

How Should Humulin N Be Stored?

Unopened vials/pens: Store at 36-46°F (2-8°C) in the refrigerator. Do not freeze. Good until printed expiration date.

In-use vials/pens: Can be stored at room temperature (below 77°F/25°C) for up to 31 days. Keep away from direct sunlight and heat.

Check before use: Inspect the insulin. Do not use if it appears clear (should be cloudy after mixing), contains particles, or is past the expiration date.

Bottom Line

Humulin N is an intermediate-acting insulin with a proven track record since 1982 for managing both Type 1 and Type 2 diabetes. To understand how it actually works in your body, see: How Does Humulin N Work? Mechanism of Action Explained in Plain English. And if you need help finding it in stock, medfinder can locate it near you.