Insulin glarginePA study guide

Why they happen and how to manage them

Hypoglycemia, including nocturnal lows

Insulin action exceeds glucose supply; the long duration can prolong recovery. Management: Treat with glucose or glucagon; review dose, meals, activity, and interacting drugs; observe longer.

Hypokalemia

Insulin shifts potassium into cells. Management: Monitor potassium in at-risk patients and replace.

Lipodystrophy and erratic absorption

Repeated injections into the same site. Management: Rotate sites; moving to fresh tissue can raise absorption, so watch for lows.

Weight gain and edema

Anabolic effects, less glucose lost in urine, and sodium retention. Management: Adjust the regimen; watch for heart failure with thiazolidinediones.

Sources: [1][2][3][4]

Common and serious

Sources: [1][2][3][4][5][6][7]

Narrow therapeutic index

The label does not describe a narrow therapeutic index or direct dosing by measured blood levels of the drug.

Sources: [1]

Blood glucose

Why

Hypoglycemia and dose titration

When

More often with regimen changes, renal or hepatic impairment, hypoglycemia unawareness, and interacting drugs

Act on

Do not give during hypoglycemia; treat lows with carbohydrate, glucagon, or IV glucose

Normal

Fasting 70 to 99 mg/dL.

Sources: [1][2][3][4][5]

Hemoglobin A1c

Why

Long-term glycemic control

When

Periodically per diabetes care standards

Normal

Below 5.7% is normal and 6.5% or higher indicates diabetes. Many people with diabetes aim for below 7%.

Sources: [1]

Potassium

Why

Insulin-induced hypokalemia

When

In patients at risk, such as those on potassium-lowering drugs

Act on

Treat hypokalemia

Normal

3.7 to 5.2 mEq/L.

Sources: [1][2]

Adult dose

Type 1 diabetes, starting

About one-third of the total daily insulin need, once daily; give the rest as short-acting premeal insulin.

Type 2 diabetes, insulin-naive

0.2 units/kg or up to 10 units once daily, then individualize.

Switching from NPH

Once-daily NPH: same dose. Twice-daily NPH: 80% of the total NPH dose, once daily.

Switching from glargine 300 units/mL (Toujeo)

80% of the Toujeo dose, once daily.

Sources: [1][2]

Renal adjustment

No fixed adjustment; not studied. Insulin levels can rise in kidney failure, so check glucose often and adjust as needed.

Sources: [1]

Hepatic adjustment

No fixed adjustment; not studied. Hypoglycemia risk is higher, so check glucose often and adjust as needed.

Sources: [1][2]

Boxed warning

None on the current Lantus label.

Sources: [1]

Contraindications

• During episodes of hypoglycemia
• Hypersensitivity to insulin glargine or any excipient

Sources: [1]

Key interactions

Other diabetes drugs (including GLP-1 agonists, DPP-4 and SGLT-2 inhibitors), ACE inhibitors, ARBs, fibrates, fluoxetine, MAO inhibitors, salicylates, sulfonamide antibiotics, octreotide, pramlintide

Raise hypoglycemia risk; dose cuts may be needed.

Corticosteroids, diuretics, atypical antipsychotics, estrogens and oral contraceptives, thyroid hormones, sympathomimetics such as albuterol, protease inhibitors, isoniazid, niacin

Blunt the glucose-lowering effect; dose increases may be needed.

Alcohol, beta blockers, clonidine, lithium; pentamidine

May push glucose up or down.

Beta blockers, clonidine, guanethidine, reserpine

Can hide the warning signs of hypoglycemia.

Thiazolidinediones (pioglitazone)

Fluid retention that can cause or worsen heart failure.

Sources: [1][2]

Antidote or reversal

Hypoglycemia: oral carbohydrate for mild episodes; glucagon or concentrated IV glucose for coma, seizures, or neurologic impairment. Keep observing and feeding carbohydrates, since the long action can bring lows back. Correct hypokalemia.

Sources: [1][2]

Pregnancy

Published studies have not shown a clear link to birth defects, miscarriage, or poor outcomes. Poorly controlled diabetes in pregnancy raises the risk of DKA, preeclampsia, birth defects, and stillbirth.

Sources: [1]

Lactation

Little or no data on glargine in human milk; natural insulin is present in milk. Weigh breastfeeding benefits against maternal need.

Sources: [1]

Pediatric

Effective and safe in children; studied in ages 6 to 15 with type 1 diabetes. Children had more severe hypoglycemia than adults in trials, so monitor glucose closely.

Sources: [1]

Geriatric

No overall differences in trials, but use conservative starting doses, increments, and maintenance doses. Hypoglycemia may be harder to recognize in older adults.

Sources: [1]