What is Lantus (insulin glargine)?

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What is Lantus?

Lantus is the brand name for insulin glargine, a long-acting basal insulin analog used to control blood glucose in adults and children with type 1 and type 2 diabetes mellitus. 1

Pharmacological Classification and Mechanism

  • Insulin glargine is a recombinant human insulin analog produced through DNA technology using a nonpathogenic strain of Escherichia coli, with modifications at position A21 and the C-terminus of the B-chain that create unique pharmacokinetic properties. 2, 3

  • The drug provides a relatively constant, peakless basal insulin profile over approximately 24 hours, distinguishing it from intermediate-acting insulins like NPH. 4, 2

  • Onset of action occurs at approximately 1 hour after subcutaneous injection, with duration of action lasting up to 24 hours, allowing for once-daily dosing. 5, 4

Primary Clinical Indications

  • Insulin glargine is indicated for basal glycemic control in both type 1 and type 2 diabetes mellitus, primarily functioning to restrain hepatic glucose production and limit hyperglycemia overnight and between meals. 6, 4

  • In type 1 diabetes, insulin glargine must be combined with short-acting insulin analogs to cover prandial (mealtime) insulin needs as part of a basal-bolus regimen. 5, 4

  • In type 2 diabetes, insulin glargine is typically added when oral antidiabetic agents fail to achieve glycemic targets, often used in combination with metformin and possibly one additional non-insulin agent. 5

Key Clinical Advantages

  • Insulin glargine demonstrates significantly reduced risk of symptomatic and nocturnal hypoglycemia compared to NPH insulin (26% reduction in nocturnal hypoglycemia, 46% reduction in severe hypoglycemia), while achieving equivalent glycemic control. 6, 7

  • The peakless profile results in more stable glycemic control and improved reproducibility of plasma insulin levels compared to conventional human insulins. 2, 8

Administration Guidelines

  • Insulin glargine should be administered once daily at the same time each day (though it can be given at any time of day with similar efficacy), injected subcutaneously in the upper legs, upper arms, or abdomen. 5, 1

  • Do not dilute or mix insulin glargine with any other insulin or solution due to its low pH formulation. 5

  • Injection sites should be rotated within the chosen area to reduce risk of lipodystrophy and localized cutaneous amyloidosis. 1

Important Safety Considerations

  • Never share insulin glargine pens or syringes between patients, even if the needle is changed, due to risk of transmission of blood-borne pathogens. 1

  • Hypoglycemia is the most common adverse reaction with insulin glargine, though the risk is lower than with NPH insulin, particularly for nocturnal episodes. 1, 7

  • Always check the insulin label before each injection to reduce the risk of medication errors. 1

Available Formulations

  • Lantus is available as U-100 insulin glargine (100 units/mL) in both vials and SoloStar prefilled pens. 1

  • Concentrated U-300 glargine formulations (Toujeo) are available for patients requiring larger doses, offering longer duration of action but requiring approximately 10-18% higher daily doses compared to U-100 glargine. 5

References

Research

Insulin glargine (Lantus).

International journal of clinical practice, 2002

Guideline

Insulin Glargine Pharmacokinetics and Clinical Implications

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Guideline

Insulin Glargine Dosing and Administration

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

[Medication of the month. Insulin glargine (Lantus)].

Revue medicale de Liege, 2004

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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