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Insulin subcutaneous suspension (human recombinant 100 units/mL)

Insulin isophane

Generic name: insulin isophane

Brand names: HumuLIN N, HumuLIN N KwikPen, NovoLIN N, ReliOn/NovoLIN N, Insulin Purified NPH Pork, Iletin II NPH Pork, Iletin NPH, HumuLIN N Pen, NovoLIN N PenFill, NovoLIN N Innolet, NovoLIN N FlexPen, ReliOn/NovoLIN N FlexPen

Last updated November 2, 2026 0 views
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What is insulin isophane?

Insulin is a hormone that helps lower glucose (sugar) levels in the blood. Insulin isophane is an intermediate-acting insulin that begins to work within 2 to 4 hours after injection, reaches its highest effect in 4 to 12 hours, and continues to work for 12 to 18 hours.

Insulin isophane is used to help control blood sugar levels in adults and children with diabetes mellitus.

Insulin isophane may also be used for other purposes not mentioned in this medication guide.

This section was rewritten for readability and reviewed for meaning.

Warnings

You should not use insulin isophane if you are having low blood sugar.

Never share an injection pen or syringe with anyone else, even if the needle has been replaced.

This section was rewritten for readability and reviewed for meaning.

Before taking this medicine

You should not use insulin isophane if you are allergic to it, or if you are experiencing low blood sugar (hypoglycemia).

Do not give insulin isophane to a child without a doctor's advice.

Tell your doctor if you have ever had:

  • liver or kidney disease; or
  • low potassium levels in your blood (hypokalemia).

Tell your doctor if you also take pioglitazone or rosiglitazone (sometimes included with glimepiride or metformin). Taking certain oral diabetes medicines while using insulin may increase your risk of serious heart issues.

Tell your doctor if you are pregnant or breastfeeding.

Follow your doctor's instructions about using insulin if you are pregnant or become pregnant. Managing diabetes is very important during pregnancy, and having high blood sugar may lead to complications for both the mother and the baby.

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Insulin isophane side effects

Get emergency medical help if you have signs of an insulin allergy: redness or swelling at the injection site, itchy skin rash all over your body, trouble breathing, chest tightness, feeling faint, or swelling of your tongue or throat.

Insulin isophane may cause serious side effects. Call your doctor immediately 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 feeling limp.

Common side effects of insulin isophane 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 the FDA at 1-800-FDA-1088.

This section was rewritten for readability and reviewed for meaning.

How should I use insulin isophane?

Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.

Insulin isophane is injected under the skin. A healthcare provider can teach you how to properly use the medication by yourself.

Insulin isophane 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 insulin isophane 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. Ask your doctor or pharmacist if you don't understand all instructions.

Insulin isophane 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 insulin isophane. 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 insulin isophane. 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.

You may have low blood sugar (hypoglycemia) and feel very hungry, dizzy, irritable, confused, anxious, or shaky. To quickly treat hypoglycemia, eat or drink a fast-acting source of sugar (fruit juice, hard candy, crackers, raisins, or non-diet soda).

Your doctor may prescribe a glucagon injection kit in case you have severe hypoglycemia. Be sure your family or 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.

Insulin isophane 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) insulin isophane:

  • 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) insulin isophane:

  • 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 insulin isophane 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. If it is almost time for your next dose, skip the missed dose. Do not use two doses at the same time.

Get your prescription refilled before you run out of medicine completely.

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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.

Insulin can cause low blood sugar. Avoid driving or operating machinery until you know how insulin isophane will affect you.

Avoid medication errors by always checking the medicine label before injecting your insulin. Some brands of insulin isophane and syringes can be used in place of others, while some cannot. 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.

This section was rewritten for readability and reviewed for meaning.

What other drugs will affect insulin isophane?

Insulin isophane may not be as effective when taken with other medicines at the same time. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Certain drugs can also reduce your symptoms of hypoglycemia, making it harder to notice when your blood sugar is low. Not all possible interactions are mentioned here. Inform your doctor about all medicines you begin or discontinue.

This section was rewritten for readability and reviewed for meaning.

Common questions about insulin isophane

How and where should I inject insulin?
Injecting insulin is not difficult, but it does take a bit of practice. There are three main sites where insulin can be injected: the stomach area except for a 2-inch circle around your navel, and the soft part of your waist, but not anywhere near your spine; the top and outer part of your thighs, but not your inner thighs or anywhere close to your knee; the outer back of your upper arm where there is a pocket of fatty tissue. Continue reading
Can Trulicity be used with insulin?
Trulicity can be used with insulin, but because the combination of Trulicity and insulin increases the risk of low blood sugar levels (hypoglycemia), the dosage of insulin may need to be reduced. Continue reading
What are the different types of insulin?
Insulins are usually grouped as fast-acting, intermediate-acting, or long-acting. Within these groups, they can be further classified as human insulin and human insulin analogs. An insulin analog is a human insulin that has one or two amino acids changed which affects how quickly it is absorbed after injection and how fast or slow it acts. Insulin analogs are usually given within 15 minutes of a meal or at the same time as food. Continue reading

Related medicines

Before you take this medicine: the information on this page is general and may not cover your personal circumstances. Read the label supplied with your medicine and ask a pharmacist or doctor if you are unsure, especially if you are pregnant, breastfeeding, taking other medicines or managing a long-term condition.
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Content is provided for education and is not medical advice. See our medical disclaimer.