Indications of Insulin Glargine

Insulin glargine is indicated to improve glycemic control in adult and pediatric patients (≥6 years) with type 1 or type 2 diabetes mellitus. 1

Primary Indications by Diabetes Type

Insulin glargine must be used concomitantly with short-acting (prandial) insulin in all patients with type 1 diabetes 1
The recommended starting dosage is approximately one-third of total daily insulin requirements, with rapid-acting insulin covering the remaining two-thirds 1
Using insulin glargine alone without prandial insulin coverage would fail to control postprandial glucose excursions and lead to persistent hyperglycemia, placing patients at high risk for diabetic ketoacidosis 2
Most individuals with type 1 diabetes should be treated with multiple daily injections combining prandial and basal insulin 2

Insulin glargine is indicated when oral antidiabetic agents fail to achieve glycemic targets 3
The recommended starting dosage in insulin-naive patients is 0.2 units/kg or up to 10 units once daily 1
Insulin glargine can be used alone or in combination with oral antidiabetic agents or GLP-1 receptor agonists in type 2 diabetes 3
When basal insulin is optimally titrated to acceptable fasting glucose but A1C remains elevated, adding prandial insulin or GLP-1 receptor agonist is recommended rather than continuing to escalate basal insulin alone 3

Administer subcutaneously once daily at any time of day, but at the same time every day 1
Inject into the abdominal area, thigh, or deltoid, rotating injection sites within the same region 1
Do not administer intravenously or via an insulin pump 1
Do not dilute or mix insulin glargine with any other insulin or solution 1

Total daily insulin requirements typically range from 0.4 to 1.0 units/kg/day, with higher doses (≥1 unit/kg/day) often needed in type 2 diabetes due to insulin resistance 3
Dosage adjustments are needed with changes in physical activity, meal patterns, acute illness, or changes in renal or hepatic function 1
If basal insulin dose exceeds 0.5 units/kg/day and A1C remains above target, consider advancing to combination injectable therapy with GLP-1 receptor agonists or adding prandial insulin 3

Frequent glucose monitoring and dosage adjustment may be necessary in patients with kidney impairment, as some studies with human insulin have shown increased circulating insulin levels in patients with kidney failure 1

Frequent glucose monitoring and dosage adjustment may be necessary in patients with hepatic impairment 1

Initial dosing, dosage increments, and maintenance dosage should be conservative to avoid hypoglycemic reactions 1
Hypoglycemia may be difficult to recognize in geriatric patients 1
Elderly hospitalized patients with reduced oral intake should start with reduced total daily dose of 0.1-0.15 units/kg/day, given mainly as basal insulin 3

Safety and effectiveness have been established in pediatric patients aged ≥6 years with diabetes mellitus 1
Pediatric patients with type 1 diabetes had a higher incidence of severe symptomatic hypoglycemia compared to adults 1
During puberty, insulin requirements may increase dramatically to as much as 1.5 units/kg per day due to hormonal influences 3

Insulin glargine provides a relatively constant, peakless basal insulin profile with duration of action up to 24 hours 3, 4
Significantly lower risk of hypoglycemia, especially nocturnal hypoglycemia, compared to NPH insulin while achieving equivalent glycemic control 3, 4, 5
More consistent absorption than intermediate-acting insulins like NPH 3
Once-daily dosing improves treatment satisfaction and adherence 4, 5

Insulin glargine is not recommended for the treatment of diabetic ketoacidosis 1
Contraindicated during episodes of hypoglycemia 1
Contraindicated in patients with hypersensitivity to insulin glargine or any excipients 1
In some patients, glargine may not last 24 hours, and dividing the dose into two daily injections should be considered 3

Increase frequency of blood glucose monitoring during changes to insulin regimen 1
Titration should be based on home glucose monitoring or A1C levels 3
Close blood glucose monitoring is essential when initiating or changing insulin regimens, with dose adjustments based on glucose patterns 3