insulin glargine (rDNA origin) injection
Lantus

Available forms
Available by prescription only
Injection: 100 units/ml

Indications and dosages
 Management of type 1 diabetes mellitus in patients who need basal (long-acting) insulin for the control of hyperglycemia. Adults and children older than age 6: Individualize dosage and administer S.C. once daily h.s.
 Management of type 2 diabetes mellitus in patients who need basal (long-acting) insulin for control of hyperglycemia. Adults: Individualize dosage and administer S.C. once daily h.s.

Pharmacodynamics
Antidiabetic action: Regulates glucose metabolism by stimulating peripheral glucose uptake, especially by skeletal muscle and fat, and by inhibiting hepatic glucose production.

Pharmacokinetics
Absorption: After S.C. injection of insulin glargine in healthy subjects and in patients with diabetes, the insulin serum levels indicated a slower, more prolonged absorption and a relatively constant level/time profile over 24 hours with no pronounced peak compared with NPH insulin.
Distribution: No information available.
Metabolism: Partly metabolized to form two active metabolites with in vitro activity similar to that of insulin.
Excretion: No information available.

Contraindications and precautions
Lantus is contraindicated in patients who are hypersensitive to insulin glargine or its excipients. Don’t use during episodes of hypoglycemia. Use cautiously in patients with renal or hepatic impairment.

Interactions
Drug-drug. ACE inhibitors, disopyramide, fibrates, fluoxetine, MAO inhibitors, octreotide, oral antidiabetics, propoxyphene, salicylates, somatostatin analog, sulfonamide antibiotics: May cause hypoglycemia and increased insulin effect. Monitor blood glucose levels. Dosage adjustments of insulin may be required.
Albuterol, corticosteroids, danazol, diuretics, estrogens, isoniazid, phenothiazine derivatives, progestins (including hormonal contraceptives), somatropin, sympathomimetics (such as epinephrine), terbutaline, thyroid hormones: May reduce serum glucose-lowering effect of insulin. Monitor blood glucose levels. Insulin dosage may need to be adjusted.
Beta blockers, clonidine, guanethidine, reserpine: May mask signs of hypoglycemia. Use cautiously. Monitor blood glucose levels.
Beta blockers, clonidine, lithium: May potentiate or weaken serum glucose-lowering effect of insulin. Monitor blood glucose levels. Insulin dosage may need adjustment.
Pentamidine: May cause hypoglycemia, which may be followed by hyperglycemia. Use cautiously. Monitor blood glucose levels.
Drug-lifestyle. Alcohol use, emotional stress, exercise: May potentiate or weaken blood glucose-lowering effect of insulin. Monitor blood glucose levels. Dosage adjustments of insulin may be required.

Adverse reactions
Metabolic: hypoglycemia.
Skin: lipodystrophy, pruritus, rash, injection site reaction (pain).
Other: allergic reactions.

Effects on lab test results
• May decrease glucose levels.

Overdose and treatment
Hypoglycemia may result from excessive insulin dose or from lower insulin requirements caused by increased work or exercise without eating, food not being absorbed in the usual manner because of postponement or omission of a meal, or illness with vomiting, fever, or diarrhea. Symptoms may include fatigue, weakness, confusion, headache, seizures, dizziness, hunger, nausea, numbness, and pale skin.
 Mild episodes of hypoglycemia can be treated with oral glucose or other carbohydrates. Adjustments in drug dosage, meal patterns, or exercise may be needed. More severe episodes with coma, seizure, or neurologic impairment may be treated with I.M./S.C. glucagon or concentrated I.V. glucose. Sustained carbohydrate intake and observation may be needed because hypoglycemia may recur after apparent clinical recovery.

Special considerations
• Insulin glargine isn’t intended for I.V. administration. It is only for S.C. administration.
• If switching from NPH insulin to insulin glargine injection, start with 80% of total NPH units per day
• Because of the prolonged duration of insulin glargine, it isn’t the insulin of choice for diabetic ketoacidosis.
• Note that the prolonged duration of activity of insulin glargine is dependent on injection into S.C. space.
• The absorption, onset, and duration of action may be affected by exercise and other variables such as illness and emotional stress.
 ALERT Don’t confuse Lantus with Lente.
• Don’t dilute or mix insulin glargine with any other insulin or solution.
• As with any insulin therapy, lipodystrophy may occur at the site of injection and delay insulin absorption. Continuously rotate the injection site within a given area to reduce lipodystrophy.
• Hypoglycemia is the most common adverse effect of insulin. Early symptoms may be different or less pronounced in patients with long duration of diabetes, diabetic nerve disease, or intensified diabetes control. Monitor serum glucose closely in these patients because severe hypoglycemia may result before the patient develops symptoms.
• As with any insulin, the desired blood glucose levels as well as the doses and timing of antidiabetics must be determined individually. Blood glucose monitoring is recommended for all patients with diabetes.
Breast-feeding patients
• It isn’t known whether insulin glargine appears in significant amounts in breast milk. Because many drugs do, including human insulin, use cautiously in breast-feeding women.
• Breast-feeding women may need adjustments in insulin dose and diet.
Pediatric patients
• Safety and effectiveness have been established in children ages 6 to 15 with type 1 diabetes.
• Administration in children younger than age 6 hasn’t been studied.
• Based on the results of clinical trials, dosage recommendations for children are the same as for adults.
Geriatric patients
• Because hypoglycemia may be difficult to recognize in elderly patients with diabetes, the initial dosing, dose increments, and maintenance dosage should be conservative to avoid hypoglycemic reactions.

Patient education
• Educate patient on proper blood glucose monitoring techniques and proper diabetes management.
 ALERT Educate diabetic patients on the signs and symptoms of hypoglycemia, such as fatigue, weakness, confusion, headache, and pale skin.
• Advise patient to treat mild episodes of hypoglycemia with oral glucose tablets. Encourage patient to always carry glucose tablets in case of a hypoglycemic episode.
• Teach patient the importance of maintaining a diabetic diet and that adjustments in drug dosage, meal patterns, and exercise may be needed to regulate serum glucose.
 ALERT Tell patient that any change of insulin should be made cautiously and only under medical supervision. Advise him that changes in insulin, strength, manufacturer, type (for example, regular, NPH, or insulin analogs), species (animal, human), or method of manufacturer (rDNA versus animal source insulin) may result in the need for a change in dosage and that the dosage of oral antidiabetics also being taken may need to be adjusted.
• Tell patient not to use OTC products without medical approval.
 ALERT Warn patient not to dilute or mix any other insulin or solution with insulin glargine. If the solution is cloudy, advise patient to discard the vial.
• Tell patient to store unopened vials and cartridges in the refrigerator.

Reactions may be common, uncommon, life-threatening, or COMMON AND LIFE THREATENING.
◆ Canada only
◇ Unlabeled clinical use