Is Semglee a Long-Acting Insulin?
Yes, Semglee (insulin glargine) is definitively a long-acting insulin analog designed to provide basal insulin coverage over 24 hours. 1
Classification and Pharmacological Profile
Insulin glargine is FDA-approved as a long-acting human insulin analog indicated to improve glycemic control in adult and pediatric patients with diabetes mellitus 1
The pharmacokinetic profile demonstrates an onset of action at approximately 1 hour, no pronounced peak, and a duration of action of approximately 24 hours, which distinguishes it from intermediate-acting insulins like NPH 2, 3
This peakless, flat time-action profile provides relatively constant basal insulin levels throughout the day and night, making it ideal for once-daily dosing 3, 4
Clinical Characteristics
Insulin glargine slowly releases insulin over 24 hours, creating more physiologic basal insulin levels compared to intermediate-acting insulins 2, 3
The absence of a pronounced peak action time reduces the risk of hypoglycemia, particularly nocturnal hypoglycemia, compared to NPH insulin 2, 3, 5
It is absorbed more consistently than intermediate-acting insulins like NPH, providing more stable glycemic control 2, 6
Comparison to Other Insulin Types
The American Academy of Family Physicians classifies insulin glargine distinctly as long-acting 2:
| Insulin Type | Onset | Peak | Duration |
|---|---|---|---|
| Rapid-acting (lispro, aspart) | 5 minutes | 1-2 hours | 3-4 hours |
| Regular (short-acting) | 15 minutes | 3-4 hours | 6-8 hours |
| Intermediate-acting (NPH) | 1 hour | 6-8 hours | 12 hours |
| Long-acting (glargine) | 1 hour | None | 24 hours |
Administration Guidelines
Administer subcutaneously once daily at any time of day, but at the same time every day to maintain stable blood glucose levels 7, 1
Do not dilute or mix with any other insulin or solution due to its low pH diluent 2, 1
Common injection sites include the abdominal area, thigh, or deltoid, with rotation recommended to reduce lipodystrophy risk 1
Important Clinical Caveat
- While classified as long-acting with 24-hour duration, in some patients glargine may not provide full 24-hour coverage, and dividing the dose into twice-daily injections should be considered if glycemic control is inadequate 7