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Humulin R

Generic Name: insulin regular (IN soo lin REG yoo lar)
Brand Name: HumuLIN R, Myxredlin, NovoLIN R

Medically reviewed by Philip Thornton, DipPharm. Last updated on March 26, 2021.

What is Humulin R?

Insulin is a hormone that works by lowering levels of glucose (sugar) in the blood. Humulin R is a short-acting insulin that starts to work within 30 minutes after injection, peaks in 2 to 3 hours, and keeps working for up to 8 hours.

Humulin R is used to improve blood sugar control in adults and children with diabetes mellitus.

Humulin R may be used for type 1 or type 2 diabetes.

Warnings

You should not use insulin if you are having an episode of hypoglycemia (low blood sugar).

Before taking this medicine

You should not use Humulin R if you are allergic to insulin, or if you are having an episode of hypoglycemia (low blood sugar).

Humulin R is not approved for use by anyone younger than 2 years old. Humulin R should not be used to treat type 2 diabetes in a child of any age.

To make sure Humulin R is safe for you, tell your doctor if you have ever had:

Taking certain oral diabetes medicines while using Humulin R may increase your risk of serious heart problems. Tell your doctor if you also take medicine that contains pioglitazone or rosiglitazone.

Tell your doctor if you are pregnant or breastfeeding.

Follow your doctor's instructions about using Humulin R 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 R?

Use Humulin R exactly as prescribed by your doctor. Follow all directions on your prescription label and read all medication guides or instruction sheets.

Humulin R is injected under the skin. A healthcare provider can teach you how to properly use the medication by yourself. Humulin R must not be given with an insulin pump. Do not inject Humulin R into a vein or a muscle.

Read and carefully follow any Instructions for Use provided with your medicine. Ask your doctor or pharmacist if you don't understand all instructions.

Prepare a Humulin R injection only when you are ready to give it. Do not use if the medicine looks cloudy, has changed colors, or has particles in it. Call your pharmacist for new medicine.

Prepare your injection only when you are ready to give it. Do not use if the medicine looks cloudy, has changed colors, or has particles in it. Call your pharmacist for new medicine.

Your care provider will show you where on your body to inject insulin. Use a different place each time you give an injection. Do not inject into the same place two times in a row.

Do not inject this medicine into skin that is damaged, tender, bruised, pitted, thickened, scaly, or has a scar or hard lump.

After using Humulin R, you should eat a meal within 30 minutes.

Never share a syringe with another person, even if the needle has been changed. Sharing syringes 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 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.

In case of emergency, wear or carry medical identification to let others know you have diabetes.

Keep Humulin R in its original container protected from heat and light. 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 R:

  • Refrigerate and use until expiration date; or

  • Store at room temperature and use within the number of days shown in your Instructions for Use.

Storing opened (in use) Humulin R:

  • Store at room temperature and use within the number of days shown in your Instructions for Use.

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.

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.

Keep insulin on hand at all times. Get your 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 R?

Do not change the brand of insulin or syringe you are using without first talking to your doctor or pharmacist. Some brands of insulin and syringes are interchangeable, while others are not. Your doctor and/or pharmacist know which brands can be substituted for one another.

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

Avoid medication errors by always checking the medicine label before injecting your insulin.

Avoid drinking alcohol. It can interfere with your diabetes treatment.

Humulin R side effects

Get emergency medical help if you have signs of an allergy to Humulin R: redness, swelling, sweating, itchy skin rash over the entire body, trouble breathing, fast heartbeats, feeling like you might pass out, or swelling in your tongue or throat.

Call your doctor at once if you have:

  • 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 R side effects may include:

  • low blood sugar;

  • swelling in your hands or feet;

  • weight gain; 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.

What other drugs will affect Humulin R?

Many other medicines can affect your blood sugar, or increase/decrease the effects of insulin. Some drugs can also cause you to have fewer symptoms of hypoglycemia, making it harder to tell when your blood sugar is low. Tell your doctor about all your current medicines and any medicine you start or stop using. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed here.

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Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Humulin R only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.