When does Lantus (insulin glargine) peak?

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Lantus (Insulin Glargine) Has No Peak Action Time

Insulin glargine (Lantus) has no pronounced peak action time, providing a relatively constant concentration profile over 24 hours. 1, 2

Pharmacokinetic Profile of Insulin Glargine

  • Insulin glargine has an onset of action of approximately 1 hour after subcutaneous injection 1, 2
  • Unlike intermediate-acting insulins which peak at 6-8 hours, insulin glargine maintains a relatively constant concentration/time profile over 24 hours with no pronounced peak 2
  • The duration of action is approximately 24 hours, allowing for once-daily dosing 1, 2
  • After subcutaneous injection, insulin glargine forms microprecipitates in the tissue from which small amounts are gradually released, resulting in the peakless profile 3

Clinical Advantages of the Peakless Profile

  • The absence of a peak action time reduces the risk of hypoglycemia compared to intermediate-acting insulins 4, 1
  • Insulin glargine is absorbed more consistently than intermediate-acting insulins, contributing to its stable glucose-lowering effect 4
  • The peakless profile allows for more stable blood glucose levels between meals and overnight 1
  • A study comparing glargine with NPH insulin in patients with type 1 diabetes showed that symptomatic hypoglycemia was less common in patients who used glargine (39.9% versus 49.2% over one month) 4

Comparison with Other Insulin Types

The following table highlights the pharmacokinetic differences between insulin glargine and other insulin types:

Insulin Type Onset Peak (hours) Duration (hours)
Rapid-acting (aspart, lispro) 5 minutes 1-2 3-4
Regular insulin 15 minutes 3-4 6-8
Intermediate-acting (NPH) 1 hour 6-8 12
Glargine 1 hour None 24

4, 1

Clinical Implications

  • The FDA label confirms that insulin glargine provides "a relatively constant concentration/time profile over 24 hours with no pronounced peak in comparison to NPH insulin" 2
  • The median time between subcutaneous injection and the end of pharmacological effect was 24 hours for insulin glargine, compared to 14.5 hours for NPH insulin 2
  • The peakless profile makes insulin glargine ideal for providing basal insulin coverage, as it mimics more closely the natural physiological profile of basal endogenous insulin secretion 5
  • Due to its stable profile, insulin glargine can be administered at any time of day, though consistency in timing is recommended 6, 3

Practical Considerations

  • In patients with type 1 diabetes, insulin glargine should be used in combination with rapid-acting insulin to cover prandial insulin needs 1
  • The peakless nature of insulin glargine means it does not adequately treat postprandial hyperglycemia, necessitating supplementation with short-acting insulin at mealtimes 6
  • The pharmacokinetic properties of insulin glargine allow for easier titration of basal insulin dose, facilitating adequate blood glucose control while decreasing the risk of hypoglycemia 3

References

Guideline

Insulin Glargine Pharmacokinetics and Clinical Implications

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Research

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

Revue medicale de Liege, 2004

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

An overview of insulin glargine.

Diabetes/metabolism research and reviews, 2002

Research

Insulin Glargine: a review 8 years after its introduction.

Expert opinion on pharmacotherapy, 2009

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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