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Insulin glargine

Pronunciation: IN-su-lin-GLAR-gine
Brand names: Basaglar KwikPen, Basaglar Tempo Pen, Lantus vial, Lantus Solostar pen, Semglee vial, ... show all 9 brands
Dosage form: subcutaneous injection
Drug class: Insulin

Medically reviewed by Melisa Puckey, BPharm. Last updated on Dec 6, 2023.

What is insulin glargine?

Insulin glargine is a long-acting insulin used to treat type 1 and type 2 diabetes in certain patients to improve and maintain blood glucose levels. Insulin glargine is a man-made form of human insulin that is used once daily to provide a base level of insulin that keeps working for 24 hours or longer.

Insulin glargine is available under the brand names Lantus, Basaglar, Toujeo, Semglee, and Rezvoglar

Rezvoglar, Lantus, Semglee, and Toujeo are FDA-approved to be used for use in adult and pediatric patients with type 1 and type 2 diabetes. Basasglar is FDA-approved to be used by adults for type 2 diabetes and also for adults and pediatric patients with type 1 diabetes. In patients with type 1 diabetes, insulin glargine must be used together with a short-acting insulin. 

Insulin glargine side effects

Common insulin glargine side effects may include low blood sugar, swelling, weight gain, allergic reaction, itching, rash, or thickening or hollowing of the skin where you injected the medicine (lipodystrophy).

Serious insulin glargine side effects 

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

Insulin glargine may cause other serious side effects. Call your doctor at once if you have:

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.

Warnings

Never share an injection pen, even if you changed the needle.

Before taking this medicine

You should not use insulin glargine if you are allergic to insulin, or if you are having an episode of hypoglycemia (low blood sugar) or diabetic ketoacidosis (call your doctor for treatment).

Different brands of insulin glargine are specifically approved for different age groups and different diabetes types. The safety and effectiveness of insulin glargine in pediatric patients younger than 6 years of age with type 1 diabetes and pediatric patients with type 2 diabetes has not been established. 

Tell your doctor if you have ever had:

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.

Pregnancy

Tell your doctor if you are pregnant or plan to become pregnant, as it is not known if insulin glargine will harm your unborn baby. Follow your doctor's instructions about using this medicine if you are pregnant or you become pregnant. Controlling diabetes is very important during pregnancy.

Breastfeeding

Tell your healthcare provider if you are breastfeeding or are planning to breastfeed, as it is not known if insulin glargine may harm your breastfeeding baby.

How should I use insulin glargine?

Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed. Ask your doctor or pharmacist if you don't understand how to use an injection.

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

Insulin glargine is injected under the skin, using a syringe or insulin pen, once per day at the same time of day.

Insulin can be injected into your upper legs (thighs), upper arms, or stomach area (abdomen). Do not inject into the same place two times in a row. Avoid injecting into skin that is damaged, tender, bruised, pitted, thickened, scaly, or has a scar or hard lump.

When treating type 1 diabetes, use your short-acting insulin before meals as directed by your doctor.

Insulin glargine must not be given with an insulin pump or mixed with other insulins. Do not inject insulin glargine into a vein or a muscle.

Your dose needs may change if you switch to a different brand, strength, or form of this medicine. Avoid medication errors by using only the medicine your doctor prescribes.

If you use an injection pen, use only the injection pen that comes with insulin glargine. Attach a new needle before each use. Do not transfer the insulin from the pen into a syringe.

Never share an injection pen, even if you changed the needle. Sharing these devices can pass infections from person to person.

Blood sugar can be affected by stress, illness, surgery, exercise, alcohol use, or skipping meals.

Low blood sugar (hypoglycemia) can make you feel very hungry, dizzy, irritable, or shaky. To quickly treat hypoglycemia, eat or drink hard candy, crackers, raisins, fruit juice, or non-diet soda. Your doctor may prescribe glucagon injections in case of severe hypoglycemia.

Tell your doctor if you have frequent symptoms of high blood sugar (hyperglycemia), such as increased thirst or urination. Ask your doctor before changing your medication dosage.

Wear a medical alert tag or carry an ID card to let others know you have diabetes.

Insulin glargine is available as:

Basaglar 100 units/mL is available as Basaglar KwikPen  3 mL,  BasaglarTempo Pen

3 mL

Lantus 100 units/mL is available as a Lantus multiple-dose vial 10 mL, Lantus SoloStar prefilled pen 3 mL 

Rezvoglar 100 units/mL available as Rezvoglar KwikPen prefilled pen 3 mL

Semglee  100 units/mL available as Semglee multiple-dose vial 10 mL, Semgleeprefilled pen 3 mL

Toujeo 300 units/mL available as Toujeo SoloStar prefilled pen 1.5 ml, Toujeo Max SoloStar 3 mL prefilled pen 

What happens if I miss a dose?

Call your doctor for instructions if you miss a dose. Do not use more than one dose in a 24-hour period unless your doctor tells you to.

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 severe 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 insulin glargine?

Avoid driving or hazardous activity until you know how insulin glargine will affect you. Your reactions could be impaired.

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

Avoid drinking alcohol or using medicines that contain alcohol. It may interfere with your diabetes treatment.

What other drugs will affect insulin glargine?

Many drugs can affect your blood sugar and may also affect insulin glargine. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all other medicines you use. Not all possible interactions are listed here.

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.

Storage 

Storing unopened (not in use) insulin glargine:

Storing opened (in use) insulin glargine:

General storage information

Company

Basaglar manufactured by: Eli Lilly and Company, Indianapolis, IN 46285 USA. 

Lantus manufactured by: sanofi-aventis U.S. LLC, Bridgewater, NJ 08807, A SANOFI COMPANY.

Rezvoglar manufactured by: Eli Lilly and Company, Indianapolis, IN 46285, USA.

Semglee manufactured by: Biocon Biologics Inc. 245 Main St, 2nd Floor, Cambridge, MA 02142 USA. 

Toujeo manufactured by: sanofi-aventis U.S. LLC, Bridgewater, NJ 08807, A SANOFI COMPANY.

Popular FAQ

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

Toujeo may be given at any time of the day; however, once you have chosen a time, it is best to inject Toujeo within three hours of that time every day. If needed, you can change the time you administer Toujeo, just talk to your doctor about this. Continue reading

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

Toujeo can stay out of the refrigerator for up to 56 days (8 weeks) according to the prescribing information written on 03/2023. If Toujeo if left out the refrigerator for more than 20 or 30 minutes, it should not be put back into the refrigerator. Continue reading

Soliqua is a combination of insulin glargine plus lixisenatide, and Lantus only contains insulin glargine. Both are once-daily injections that are given under the skin (subcutaneously), but Soliqua can only be used in adults with type 2 diabetes whereas Lantus may be used to treat both type 1 and type 2 diabetes in adults and children over the age of six years. Both are made by Sanofi-Aventis. Continue reading

Even though Toujeo is usually given once a day, some people may experience better blood sugar control if the dose is split and given twice a day (every 12 hours). Continue reading

There are three pens in a box of Toujeo Solostar. There are two pens in a box of Toujeo Max Solostar. Continue reading

Both Soliqua and Xultophy combine a long-acting insulin with a GLP-1 agonist: Xultopy brings together Tresiba (insulin degludec) and Victoza (liraglutide), while Soliqua combines Lantus (insulin glargine) with Adlyxin (lixisenatide). When used with diet and exercise for the treatment of type 2 diabetes, these agents can help you control blood sugar, insulin levels, and digestion and may help you lose weight. Continue reading

Toujeo is a long-acting insulin that is usually given once a day. Toujeo lasts for up to 36 hours. Continue reading

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Further information

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