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Generic name: insulin glargine

What is Lantus?

Lantus is a long-acting man-made insulin used to control high blood sugar in adults with diabetes mellitus.

  • Lantus is not for use to treat diabetic ketoacidosis.
  • It is not known if Lantus is safe and effective in children less than 6 years of age with type 1 diabetes.
  • It is not known if Lantus is safe and effective in children with type 2 diabetes.

Who should not take Lantus?

Do not use Lantus if you:

  • are having an episode of low blood sugar (hypoglycemia).
  • have an allergy to insulin glargine or any of the ingredients in Lantus. See the end of this Patient Information guide for a complete list of ingredients in Lantus.

What should I tell my healthcare provider before taking Lantus?

Before using Lantus, tell your healthcare provider about all your medical conditions including if you:

  • have liver or kidney problems.
  • take other medicines, especially ones called TZDs (thiazolidinediones).
  • have heart failure or other heart problems. If you have heart failure, it may get worse while you take TZDs with Lantus.
  • are pregnant, planning to become pregnant, or are breastfeeding. It is not known if Lantus may harm your unborn baby or breastfeeding baby.

Tell your healthcare provider about all the medicines you take including prescription and over-the-counter medicines, vitamins, and herbal supplements.

Before you start using Lantus, talk to your healthcare provider about low blood sugar and how to manage it.

How should I take Lantus?

  • Read the detailed Instructions for Use that come with your Lantus insulin.
  • Use Lantus exactly as your healthcare provider tells you to. Your healthcare provider should tell you how much Lantus to use and when to use it.
  • Know the amount of Lantus you use. Do not change the amount of Lantus you use unless your healthcare provider tells you to.
  • Check your insulin label each time you give your injection to make sure you are using the correct insulin.
  • Do not re-use needles. Always use a new needle for each injection. Re-use of needles increases your risk of having blocked needles, which may cause you to get the wrong dose of Lantus. Using a new needle for each injection lowers your risk of getting an infection.
  • You may take Lantus at any time during the day but you must take it at the same time every day.
  • Only use Lantus that is clear and colorless. If your Lantus is cloudy or slightly colored, return it to your pharmacy for a replacement.
  • Lantus is injected under the skin (subcutaneously) of your upper legs (thighs), upper arms, or stomach area (abdomen).
  • Do not use Lantus in an insulin pump or inject Lantus into your vein (intravenously).
  • Change (rotate) injection sites within the area you chose with each dose to reduce your risk of getting lipodystrophy (pits in skin or thickened skin) and localized cutaneous amyloidosis (skin with lumps) at the injection sites.
    • Do not use the exact same spot for each injection.
    • Do not inject where the skin has pits, is thickened, or has lumps.
    • Do not inject where the skin is tender, bruised, scaly or hard, or into scars or damaged skin.
  • Do not mix Lantus with any other type of insulin or liquid medicine.
  • Check your blood sugar levels. Ask your healthcare provider what your blood sugar should be and when you should check your blood sugar levels.

Your dose of Lantus may need to change because of:

  • a change in level of physical activity or exercise
  • weight gain or loss
  • increased stress
  • illness
  • change in diet
  • the medicines you take

What should I avoid while taking Lantus?

While using Lantus do not:

  • drive or operate heavy machinery, until you know how Lantus affects you.
  • drink alcohol or use over-the counter medicines that contain alcohol.
  • share your syringes with other people, even if the needle has been changed. You may give other people a serious infection, or get a serious infection from them.

What are the possible side effects of Lantus and other insulins?

Lantus may cause serious side effects that can lead to death, including:

  • Low blood sugar (hypoglycemia). Signs and symptoms that may indicate low blood sugar include:
    • dizziness or light-headedness
    • sweating
    • confusion
    • headache
    • blurred vision
    • slurred speech
    • shakiness
    • fast heartbeat
    • anxiety
    • irritability or mood change
    • hunger
  • Severe allergic reaction (whole body reaction). Get medical help right away if you have any of these signs or symptoms of a severe allergic reaction:
    • a rash over your whole body
    • trouble breathing
    • a fast heartbeat
    • sweating
  • Low potassium in your blood (hypokalemia).
  • Heart failure. Taking certain diabetes pills called TZDs (thiazolidinediones) with Lantus may cause heart failure in some people. This can happen even if you have never had heart failure or heart problems before. If you already have heart failure it may get worse while you take TZDs with Lantus. Your healthcare provider should monitor you closely while you are taking TZDs with Lantus. Tell your healthcare provider if you have any new or worse symptoms of heart failure including:
    • shortness of breath
    • swelling of your ankles or feet
    • sudden weight gain

Treatment with TZDs and Lantus may need to be changed or stopped by your healthcare provider if you have new or worse heart failure.

Get emergency medical help if you have:

  • trouble breathing
  • shortness of breath
  • fast heartbeat
  • swelling of your face, tongue, or throat
  • sweating
  • extreme drowsiness
  • dizziness
  • confusion

The most common side effects of Lantus include:

  • low blood sugar (hypoglycemia)
  • weight gain
  • allergic reactions, including reactions at your injection site
  • skin thickening or pits at the injection site (lipodystrophy)

These are not all the possible side effects of Lantus. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Drug Interactions

A total of 371 medications are known to interact with Lantus. Use the Interactions Checker Tool.

Common Interactions Checks

General information about the safe and effective use of Lantus

Medicines are sometimes prescribed for purposes other than those listed in a Patient Information leaflet. Do not use Lantus for a condition for which it was not prescribed. Do not give Lantus to other people, even if they have the same symptoms that you have. It may harm them.

This Patient Information guide summarizes the most important information about Lantus. If you would like more information, talk with your healthcare provider. You can ask your pharmacist or healthcare provider for information about Lantus that is written for healthcare professionals. For more information, go to or call 1-800-633-1610.

How should I store Lantus?

Lantus should not be stored in the freezer and should not be allowed to freeze. Discard Lantus if it has been frozen. Protect Lantus from direct heat and light.

Storage conditions are summarized below.

Not in-use (unopened) Refrigerated: (36°F–46°F [2°C–8°C])

  • 10ml multiple-dose vial: Until expiration date
  • 3ml single-patient-use SoloStar prefilled pen: Until expiration date

Not in-use (unopened) Room Temperature: (below 86°F [30°C])

  • 10ml multiple-dose vial: 28 days
  • 3ml single-patient-use SoloStar prefilled pen: 28 days

In-use (opened)

  • 10ml multiple-dose vial: 28 days Refrigerated or room temperature
  • 3ml single-patient-use SoloStar prefilled pen: 28 days Room temperature only (Do not refrigerate)

Keep Lantus and all medicines out of the reach of children.

What are the ingredients in Lantus?

Active ingredient: insulin glargine

inactive ingredients:

10 mL vial : zinc, m-cresol, glycerol, polysorbate, and water for injection

Source: National Library of Medicine. Last updated November 26, 2019.