Half-Life of Insulin Glargine (Lantus)
Insulin glargine (Lantus) has a half-life of approximately 12-24 hours, which allows for once-daily dosing as a basal insulin therapy.
Pharmacokinetic Profile
Insulin glargine has unique pharmacokinetic properties that distinguish it from other insulins:
- After subcutaneous injection, insulin glargine forms microprecipitates in the tissue (pH > 7.4) from which small amounts are gradually released 1, 2
- This results in a relatively constant concentration-time profile with no pronounced peak over 24 hours 2, 3
- The terminal elimination half-life ranges from 12 to 17 hours with repeated dosing 4
- After a single dose, the terminal half-life is approximately 9 hours in healthy volunteers 4
Clinical Implications
The pharmacokinetic profile of insulin glargine offers several clinical advantages:
- Allows for once-daily administration as basal insulin therapy 1, 2
- Can be administered at any time of day, though preferably at the same time each day for consistency 1, 5
- Provides more consistent insulin levels compared to NPH insulin, which has a more pronounced peak 2, 3
- Results in lower risk of nocturnal hypoglycemia compared to NPH insulin 2, 5
Practical Considerations
When using insulin glargine in clinical practice:
- In type 1 diabetes, it should be combined with rapid-acting insulin before meals to control postprandial hyperglycemia 1, 3
- In type 2 diabetes, it can be used in combination with oral antidiabetic agents 1
- For patients requiring insulin in hospital settings, the relatively constant profile makes it suitable for maintaining stable glycemic control 3
Special Situations
- In patients with renal impairment, the pharmacokinetics may be altered, potentially extending the half-life
- For patients undergoing surgery, the long half-life should be considered when planning perioperative insulin management
- In some cases of labile type 1 diabetes or insulin-resistant patients, twice-daily dosing may be more effective despite the long half-life 3
The long half-life and stable pharmacokinetic profile of insulin glargine make it an effective basal insulin option that provides consistent 24-hour coverage with a single daily injection.