When does Lantus (insulin glargine) peak?

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Lantus (Insulin Glargine) Peak Time

Lantus (insulin glargine) has no peak action time—it provides a relatively constant, peakless insulin concentration over 24 hours. 1, 2, 3

Pharmacokinetic Profile

  • Onset of action: Approximately 1 hour after subcutaneous injection 1, 2
  • Peak: None—no pronounced peak in plasma insulin levels 1, 2, 3
  • Duration: Approximately 24 hours 1, 2, 3

Clinical Significance of the Peakless Profile

The absence of a peak is the defining characteristic that distinguishes Lantus from intermediate-acting insulins like NPH. 1, 2

  • The peakless profile results from insulin glargine's unique formulation: it is soluble at acidic pH (4.0) but precipitates in the neutral pH of subcutaneous tissue, creating microprecipitates that slowly release insulin 4, 5, 6

  • This provides a relatively constant concentration/time profile over 24 hours, mimicking physiologic basal insulin secretion more closely than NPH insulin 3, 5

  • The lack of peak significantly reduces the risk of hypoglycemia, particularly nocturnal hypoglycemia, compared to NPH insulin. 1, 2, 4, 5, 6

Comparison with Other Insulins

The following table demonstrates how Lantus differs from other insulin types 1, 2:

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
NPH (intermediate-acting) 1 hour 6-8 12
Lantus (glargine) 1 hour None 24

Important Clinical Caveats

  • The time course of action may vary between individual patients and even within the same patient over time. 3

  • Lantus provides basal insulin coverage only and does not address postprandial glucose excursions—it must be combined with rapid-acting or short-acting insulin at mealtimes for complete glycemic control 1, 7

  • The peakless profile allows for once-daily administration at any time of day (bedtime, morning, or other convenient time), though consistency in timing is recommended 1, 7, 6

References

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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