Insulin glargine

Pronunciation: IN-su-lin GLAR-jeen.

Generic name
insulin glargine
Drug class
Long-acting (basal) insulin analogue
Form
Injection (vial, cartridge, or pre-filled pen), 100 units/mL
Route
Subcutaneous injection
Legal status
Prescription-only

Availability and supply rules vary by country

Trade names by country: United States · United Kingdom · Canada · Australia · New Zealand

Australia: Lantus (5) · Full directory

What insulin glargine is and how it works

Insulin glargine is a prescription-only long-acting insulin used to help control blood sugar in diabetes. It is given once daily and provides a steady background level of insulin over about 24 hours. (1)

Take insulin glargine exactly as your prescriber directs, at the same time each day. Your exact dose is individually worked out based on your blood sugar readings and needs -- it is not a fixed dose for everyone.

Mechanism of action: how insulin glargine works

Insulin glargine is a long-acting insulin analogue that precipitates at the neutral pH of subcutaneous tissue after injection, forming a depot that releases insulin slowly and relatively steadily over approximately 24 hours. (1)

What insulin glargine is used for

Type 1 and type 2 diabetes

Used to improve blood sugar control in adults and children with diabetes. Not used to treat diabetic ketoacidosis (a diabetes emergency), which needs a different, faster-acting insulin. (1)

Before taking insulin glargine

Do not take / not appropriate for

  • Do not use insulin glargine during an episode of low blood sugar (hypoglycaemia). (all countries) (1)
  • Do not use insulin glargine if you have had a serious allergic reaction to it or any of its ingredients. (all countries) (1)

Tell your clinician about

  • Any history of low blood sugar episodes, and how you usually recognise and treat them.
  • Any kidney or liver problems, which can change how much insulin you need.
  • All other medicines you take, including other diabetes medicines and any 'glitazone' tablets (thiazolidinediones).
  • Pregnancy, plans for pregnancy, or breastfeeding.
(1)

How to take insulin glargine

  • Inject under the skin (abdomen, thigh, or upper arm) once a day, at the same time each day.
  • Never share your insulin pen or needle with anyone else, even if the needle is changed -- this can spread infections.
  • Rotate your injection site each time within the same general area, to help prevent skin/fat changes at injection sites.
  • Do not mix insulin glargine with other insulins in the same syringe or dilute it.
(1)

Procedures and treatment changes

Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician. (1) (2) (3) (4) (5) (6)

Missed dose

Contact your prescriber or diabetes care team for specific guidance if you miss a dose, since this depends on your individual insulin regimen and blood sugar readings.

Overdose

Seek urgent medical attention if you think you have taken too much insulin, or if you have symptoms of severe low blood sugar such as confusion, seizures, or loss of consciousness. (1)

Side effects

Side effects and their urgency vary; report severe, persistent, or concerning symptoms.

Low blood sugar (hypoglycaemia) is the most common side effect.

What to notice: Low blood sugar (hypoglycaemia) is the most common side effect.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)

Weight gain.

What to notice: Weight gain.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)

Injection site reactions, itching, and rash.

What to notice: Injection site reactions, itching, and rash.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)

Skin/fat changes (lipodystrophy) at injection sites if not rotated.

What to notice: Skin/fat changes (lipodystrophy) at injection sites if not rotated.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)

Serious warnings

Signs of low blood sugar (hypoglycaemia) — emergency

Symptoms: Shakiness, sweating, confusion, dizziness, a fast heartbeat, or, if severe, seizures or loss of consciousness.

Action: Treat low blood sugar promptly as you have been taught (usually fast-acting sugar). Seek emergency help for severe symptoms or loss of consciousness. (1)

Signs of fluid retention or heart failure (if also taking a 'glitazone' diabetes tablet) — high caution

Symptoms: Swelling in the legs or ankles, sudden weight gain, or shortness of breath.

Action: Tell your prescriber promptly -- combining insulin with thiazolidinedione medicines can increase this risk. (1)

Signs of a serious allergic reaction — emergency

Symptoms: Swelling of the face, lips, tongue, or throat; difficulty breathing; widespread rash or hives.

Action: Seek emergency medical help immediately. (1)

Interactions

  • Other diabetes medicines, ACE-inhibitor blood pressure medicines, and fibrate cholesterol medicines can increase the risk of low blood sugar. (1)
  • Steroid medicines and some diuretics ('water tablets') can reduce insulin's blood-sugar-lowering effect. (1)
  • Beta-blocker medicines can mask the warning signs of low blood sugar, such as a fast heartbeat. (1)

Pregnancy, breastfeeding, kidney/liver function, age

Pregnancy

There is limited published data on insulin glargine in pregnancy, without a clear link to problems. Good blood sugar control during pregnancy is important, and the benefits generally outweigh uncertain risks -- discuss with your prescriber. (1) (2) (3) (4) (5) (6)

Breastfeeding

Insulin is a normal part of human breast milk. Discuss the benefits and risks with your prescriber. (1) (2) (3) (4) (5) (6)

Children

Approved for children with diabetes from age 2 in some countries (age thresholds vary slightly). (1) (2) (3) (4) (5) (6)

Elderly

No specific dose adjustment based on age alone is described in the source reviewed, but insulin needs are individually monitored regardless of age. (1) (2) (3) (4) (5) (6)

Hepatic_impairment

Liver problems can change insulin requirements -- tell your prescriber about any liver issues. (1) (2) (3) (4) (5) (6)

Renal_impairment

Kidney problems can change insulin requirements -- tell your prescriber about any kidney issues. (1) (2) (3) (4) (5) (6)

Monitoring

Before starting

  • Baseline blood sugar (HbA1c)
  • Kidney and liver function where relevant
  • Review of other diabetes medicines

During treatment

  • Regular blood sugar monitoring to guide dose adjustments.
  • Periodic HbA1c checks.
  • Watching injection sites for skin/fat changes.
(1)

Storage

Refrigerate unopened vials/pens at 36-46°F (2-8°C) until the expiry date. Once in use, keep at room temperature or refrigerated for up to 28 days, then discard. Do not freeze -- discard if it has been frozen. Protect from heat and direct light.

Professional information

Clinician-facing context only, sourced from the current US FDA prescribing information; verify against the current full label before prescribing.

United States

Indication: Type 1 and type 2 diabetes

Dose summary: Once daily SC at a consistent time; individualised based on metabolic needs and glucose monitoring. Type 1: approx. one-third of total daily insulin requirement. Type 2 (insulin-naive): approx. 0.2 units/kg or up to 10 units daily as a starting point. Not for diabetic ketoacidosis. Do not dilute or mix with other insulins.

Renal context: Not established in the source reviewed for this dossier; renal impairment can alter insulin requirements and should prompt closer monitoring. (1)

Mechanism of action

Hepatic guidance

Hepatic impairment can alter insulin requirements; monitor closely.

Overdose note

Severe or prolonged hypoglycaemia can result from overdose; manage with appropriate glucose replacement and monitoring, including for milder episodes that may require adjustment of food intake and monitoring. (1)

Frequently asked questions

Is insulin glargine (Lantus) available in the US, UK, Europe, Canada, Australia, and New Zealand?

Yes, it is approved and available in all of these regions. Always consult your healthcare provider for personalised medical advice regarding your specific condition and treatment plan. Do not make changes to your medication regimen without professional medical guidance. (1) (2) (3) (4) (5) (6)

Can I reuse my insulin pen needle or share my pen with someone else?

Never share an insulin pen or needle with another person, even if you change the needle -- this can spread blood-borne infections. Follow your prescriber's guidance on how often to change needles. (1)

Why do I need to rotate my injection sites with Lantus?

Injecting into the same small area repeatedly can cause skin and fat changes (lipodystrophy) or, rarely, a localised skin condition that can make the insulin work less predictably if injected there. Rotate sites within the recommended areas (such as the abdomen, thigh, or upper arm) as your prescriber advises. (1)

What is the mechanism of action of insulin glargine?

Insulin glargine is a long-acting insulin analogue that precipitates at the neutral pH of subcutaneous tissue after injection, forming a depot that releases insulin slowly and relatively steadily over approximately 24 hours. (1)

What is the generic name of Insulin glargine?

The generic name is insulin glargine. (1)

What class of drug is insulin glargine?

Insulin glargine is classed as: Long-acting (basal) insulin analogue. (1)

References

  1. LANTUS (insulin glargine) injection -- full prescribing informationU.S. Food and Drug Administration / DailyMed (NIH), full prescribing information, Sanofi-Aventis U.S. LLC · United States · accessed 2026-07-29 · source 1
  2. Lantus European Public Assessment Report (EPAR)European Medicines Agency (EMA) · European Union · accessed 2026-07-29 · source 2
  3. Lantus 100 units/ml solution for injection -- Summary of Product Characteristicselectronic medicines compendium (emc), United Kingdom -- Sanofi · United Kingdom · accessed 2026-07-29 · source 3
  4. Lantus (insulin glargine) Product MonographHealth Canada product monograph · Canada · accessed 2026-07-29 · source 4
  5. Lantus Cartridge -- ARTG registrationTherapeutic Goods Administration (TGA), Australia · Australia · accessed 2026-07-29 · source 5
  6. Lantus New Zealand Data SheetMedsafe (New Zealand regulator) · New Zealand · accessed 2026-07-29 · source 6

Brand names by country

Single-ingredient insulin glargine names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.

Priority countries

United States

  • Lantus100 [iU]/mL · sanofi-aventis u.s. llc
  • TOUJEO300 U/mL · sanofi-aventis u.s. llc
  • Rezvoglar KwikPen100 [iU]/mL · eli lilly and company
  • SEMGLEE100 [iU]/mL · biocon biologics inc.
  • Insulin glargine U-300300 [iU]/mL · sanofi-aventis u.s. llc
  • BASAGLAR KwikPen100 [iU]/mL · eli lilly and company
  • LANGLARA100 [iU]/mL · lanexa biologics, llc

United Kingdom

  • Lantus (3)MHRA licensed emc smpc confirmed · 100 units/mL · Sanofi

Canada

  • LANTUS
  • BASAGLAR
  • TOUJEO

Australia

  • Lantus (5)TGA ARTG registered 2023-04-12 confirmed · not specified in fetched source · Sanofi-Aventis Australia Pty Ltd

New Zealand

  • Lantus (6)Medsafe approved confirmed · 100 IU/mL · Sanofi-Aventis New Zealand Limited
View brands in additional countries.

European Union

Lantus (2)

This page provides general reference information about insulin glargine and is not a substitute for advice from the prescriber managing your treatment. All dosing and treatment decisions should be made with your prescriber.

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