Generic Name: insulin isophane (IN soo lin EYE soe fane)
Brand Name: Humulin N, Novolin N
Medically reviewed by Sanjai Sinha, MD. Last updated on May 27, 2020.
What is Humulin N?
Humulin N (insulin isophane) is a man-made form of a hormone that is produced in the body. Insulin is a hormone that works by lowering levels of glucose (sugar) in the blood. Insulin isophane is an intermediate-acting insulin that starts to work within 2 to 4 hours after injection, peaks in 4 to 12 hours, and keeps working for 12 to 18 hours.
Humulin N is used to improve blood sugar control in adults and children with diabetes mellitus.
Humulin N may also be used for purposes not listed in this medication guide.
You should not use Humulin N if you are having an episode of low blood sugar.
Never share an injection pen or syringe with another person, even if the needle has been changed.
Hypoglycemia, or low blood sugar, is the most common side effect of Humulin N. Symptoms of low blood sugar may include headache, hunger, sweating, pale skin, irritability, dizziness, feeling shaky, or trouble concentrating. Watch for signs of low blood sugar. Carry a piece of non-dietetic hard candy or glucose tablets with you in case you have low blood sugar.
Humulin N side effects
Get emergency medical help if you have any signs of an allergic reaction to Humulin N: redness or swelling where an injection was given, itchy skin rash over the entire body, trouble breathing, chest tightness, feeling like you might pass out, or swelling in your tongue or throat.
Call your doctor at once if you have:
fluid retention - weight gain, swelling in your hands or feet, feeling short of breath; or
low potassium - leg cramps, constipation, irregular heartbeats, fluttering in your chest, increased thirst or urination, numbness or tingling, muscle weakness or limp feeling.
Common Humulin N side effects may include:
low blood sugar;
weight gain, swelling in your hands or feet;
itching, mild skin rash; or
thickening or hollowing of the skin where you injected the medicine.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
Before taking this medicine
You should not use Humulin N if you are allergic to insulin isophane, or if you are having an episode of hypoglycemia (low blood sugar).
Do not give Humulin N to a child without a doctor's advice.
To make sure Humulin N is safe for you, tell your doctor if you have ever had:
liver or kidney disease; or
low levels of potassium in your blood (hypokalemia).
Tell your doctor if you also take pioglitazone or rosiglitazone (sometimes contained in combinations with glimepiride or metformin). Taking certain oral diabetes medicines while you are using insulin may increase your risk of serious heart problems.
Tell your doctor if you are pregnant or breastfeeding.
Follow your doctor's instructions about using Humulin N if you are pregnant or you become pregnant. Controlling diabetes is very important during pregnancy, and having high blood sugar may cause complications in both the mother and the baby.
How should I use Humulin N?
Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.
Humulin N is injected under the skin. A healthcare provider can teach you how to properly use the medication by yourself.
Do not give Humulin N with an insulin pump.
Humulin N must not be given with an insulin pump, or mixed with other insulins. Do not inject into a vein or a muscle.
Do not inject this medicine into skin that is damaged, tender, bruised, pitted, thickened, scaly, or has a scar or hard lump.
Read and carefully follow any Instructions for Use provided with your medicine. Do not use Humulin N if you don't understand all instructions for proper use. Ask your doctor or pharmacist if you have questions.
Humulin N should look cloudy after mixing. Do not use the mixture if it looks clear or has particles in it. Call your pharmacist for new medicine.
Your care provider will show you where on your body to inject Humulin N. Use a different place each time you give an injection. Do not inject into the same place two times in a row.
If you use an injection pen, use only the injection pen that comes with Humulin N. Attach a new needle before each use. Do not transfer the insulin from the pen into a syringe.
Never share an injection pen or syringe with another person, even if the needle has been changed. Sharing these devices can allow infections or disease to pass from one person to another.
Low blood sugar (hypoglycemia) can happen to everyone who has diabetes. Symptoms include headache, hunger, sweating, irritability, dizziness, nausea, and feeling shaky. To quickly treat low blood sugar, always keep a fast-acting source of sugar with you such as fruit juice, hard candy, crackers, raisins, or non-diet soda.
Your doctor can prescribe a glucagon emergency injection kit to use in case you have severe hypoglycemia and cannot eat or drink. Be sure your family and close friends know how to give you this injection in an emergency.
Also watch for signs of high blood sugar (hyperglycemia) such as increased thirst or urination.
Blood sugar levels can be affected by stress, illness, surgery, exercise, alcohol use, or skipping meals. Ask your doctor before changing your dose or medication schedule.
Humulin N is only part of a complete treatment program that may also include diet, exercise, weight control, blood sugar testing, and special medical care. Follow your doctor's instructions very closely.
Keep this medicine in its original container protected from heat and light. Do not draw insulin from a vial into a syringe until you are ready to give an injection. Do not freeze insulin or store it near the cooling element in a refrigerator. Throw away any insulin that has been frozen.
Storing unopened (not in use) Humulin N:
Refrigerate and use until expiration date; or
Store at room temperature and use within the number of days specified in the Instructions for Use provided with your medicine.
Storing opened (in use) Humulin N:
Store in a refrigerator or at room temperature as directed in the Instructions for Use provided with your medicine. Do not refrigerate an in-use injection pen.
In-use Humulin N is stable for only a certain number of days. Throw away any medicine not used within that time. Follow all storage directions provided with your medicine.
Use a needle and syringe only once and then place them in a puncture-proof "sharps" container. Follow state or local laws about how to dispose of this container. Keep it out of the reach of children and pets.
In case of emergency, wear or carry medical identification to let others know you have diabetes.
What happens if I miss a dose?
Use the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not use two doses at one time.
Get your Humulin N prescription refilled before you run out of medicine completely.
What happens if I overdose?
Seek emergency medical attention or call the Poison Help line at 1-800-222-1222. Insulin overdose can cause life-threatening hypoglycemia. Symptoms include drowsiness, confusion, blurred vision, numbness or tingling in your mouth, trouble speaking, muscle weakness, clumsy or jerky movements, seizure (convulsions), or loss of consciousness.
What should I avoid while using Humulin N?
Insulin can cause low blood sugar. Avoid driving or operating machinery until you know how this medicine will affect you.
Avoid medication errors by always checking the medicine label before injecting your insulin. Some brands of insulin isophane and syringes are interchangeable, while others are not. Your doctor and/or pharmacist know which brands can be substituted for one another.
Avoid drinking alcohol. It can cause low blood sugar and may interfere with your diabetes treatment.
What other drugs will affect Humulin N?
Humulin N may not work as well when you use other medicines at the same time. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Some drugs can also cause you to have fewer symptoms of hypoglycemia, making it harder to tell when your blood sugar is low. Not all possible interactions are listed here. Tell your doctor about all medicines you start or stop using.
Frequently asked questions
- Are Humulin and Humalog the same thing?
- Is Novolin the same as Humulin?
- Humulin N vs Humulin R - What's the difference?
- Is NPH a long acting insulin?
- What kind of insulin is NPH?
More about Humulin N (insulin isophane)
- Side Effects
- During Pregnancy
- Dosage Information
- Drug Interactions
- Pricing & Coupons
- En Español
- 3 Reviews
- Drug class: insulin
- FDA Alerts (1)
- Other brands
- Novolin N
Related treatment guides
Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Humulin N only for the indication prescribed.
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
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