Humalog Pen

Action

Promotes glucose transport, which stimulates carbohydrate metabolism in skeletal and cardiac muscle and adipose tissue. Also promotes phosphorylation of glucose in liver, where it is converted to glycogen. Directly affects fat and protein metabolism, stimulates protein synthesis, inhibits release of free fatty acids, and indirectly decreases phosphate and potassium.

Availability

Glulisine, recombinant: 100 units/ml in 10-ml vials, 100 units/ml in 3-ml cartridge system, 100 units/ml in 3-ml prefilled pen

Isophane suspension, injection (regular): 70 units NPH and 30 units regular insulin/ml (100 units/ml total), 50 units NPH and 50 units regular insulin/ml (100 units/ml total)

Isophane suspension (NPH insulin): 100 units/ml

Lispro: 100 units/ml in 10-ml vials and 1.5-ml cartridges

Regular insulin injection: 100 units/ml

Regular U-500 (concentrated), insulin human injection: 500 units/ml

Zinc suspension, extended (ultralente): 100 units/ml

Zinc suspension (lente insulin): 100 units/ml

Indications and dosages

➣ Type 1 (insulin-dependent) diabetes mellitus; type 2 (non-insulin-dependent) diabetes mellitus unresponsive to diet and oral hypoglycemics

Adults and children: In newly diagnosed diabetes, total of 0.5 to 1 unit/kg/day subcutaneously as part of multidose regimen of short- and long-acting insulin. Dosage individualized based on patient's glucose level, adjusted to premeal and bedtime glucose levels. Reserve concentrated insulin (500 units/ml) for patients requiring more than 200 units/day.

➣ Diabetic ketoacidosis

Adults and children: Loading dose of 0.15 units/kg (nonconcentrated regular insulin) I.V. bolus, followed by continuous infusion of 0.1 unit/kg/hour until glucose level drops. Then administer subcutaneously, adjusting dosage according to glucose level.

Contraindications

• Hypersensitivity to drug or its components

• Hypoglycemia

Precautions

Use cautiously in:

• hepatic or renal impairment, hypothyroidism, hyperthyroidism

• elderly patients

• pregnant or breastfeeding patients

• children.

Administration

See Be aware that insulin is a high-alert drug whether given subcutaneously or I.V.

See Don't give insulin I.V. (except nonconcentrated regular insulin), because anaphylactic reaction may occur.

• When mixing two types of insulin, draw up regular insulin into syringe first.

• For I.V. infusion, mix regular insulin only with normal or half-normal saline solution, as prescribed, to yield a concentration of 1 unit/ml. Give every 50 units I.V. over at least 1 minute.

• Rotate subcutaneous injection sites to prevent lipodystrophy.

• Administer mixtures of regular and NPH or regular and lente insulins within 5 to 15 minutes of mixing.

Adverse reactions

Metabolic: hypokalemia, sodium retention, hypoglycemia, rebound hyperglycemia (Somogyi effect)

Skin: urticaria, rash, pruritus

Other: edema; lipodystrophy; lipohypertrophy; erythema, stinging, or warmth at injection site; allergic reactions including anaphylaxis

Interactions

Drug-drug. Acetazolamide, albuterol, antiretrovirals, asparaginase, calcitonin, corticosteroids, cyclophosphamide, danazol, dextrothyroxine, diazoxide, diltiazem, diuretics, dobutamine, epinephrine, estrogens, hormonal contraceptives, isoniazid, morphine, niacin, phenothiazines, phenytoin, somatropin, terbutaline, thyroid hormones: decreased hypoglycemic effect

Anabolic steroids, angiotensin-converting enzyme inhibitors, calcium, chloroquine, clofibrate, clonidine, disopyramide, fluoxetine, guanethidine, mebendazole, MAO inhibitors, octreotide, oral hypoglycemics, phenylbutazone, propoxyphene, pyridoxine, salicylates, sulfinpyrazone, sulfonamides, tetracyclines: increased hypoglycemic effect

Beta-adrenergic blockers (nonselective): masking of some hypoglycemia symptoms, delayed recovery from hypoglycemia

Lithium carbonate: decreased or increased hypoglycemic effect

Pentamidine: increased hypoglycemic effect, possibly followed by hyperglycemia

Drug-diagnostic tests. Glucose, inorganic phosphate, magnesium, potassium: decreased levels

Liver and thyroid function tests: interference with test results

Urine vanillylmandelic acid: increased level

Drug-herbs. Basil, burdock, glucosamine, sage: altered glycemic control Chromium, coenzyme Q10, dandelion, eucalyptus, fenugreek, marshmallow: increased hypoglycemic effect

Garlic, ginseng: decreased blood glucose level

Drug-behaviors. Alcohol use: increased hypoglycemic effect

Marijuana use: increased blood glucose level

Smoking: increased blood glucose level, decreased response to insulin

Patient monitoring

• Monitor glucose level frequently to assess drug efficacy and appropriateness of dosage.

• Watch blood glucose level closely if patient is converting from one insulin type to another or is under unusual stress (as from surgery or trauma).

See Monitor for signs and symptoms of hypoglycemia. Keep glucose source at hand in case hypoglycemia occurs.

See Assess for signs and symptoms of hyperglycemia, such as polydipsia, polyphagia, polyuria, and diabetic ketoacidosis (as shown by blood and urinary ketones, metabolic acidosis, extremely elevated blood glucose level).

• Monitor for glycosuria.

• Closely evaluate kidney and liver function test results in patients with renal or hepatic impairment.

Patient teaching

• Teach patient how to administer insulin subcutaneously as appropriate.

• Advise patient to draw up regular insulin into syringe first when mixing two types of insulin. Caution him not to change order of mixing insulins.

• Instruct patient to rotate subcutaneous injection sites and keep a record of sites used, to prevent fatty tissue breakdown.

See Teach patient how to recognize and report signs and symptoms of hypoglycemia and hyperglycemia. Advise him to carry a glucose source at all times.

• Instruct patient to store insulin in refrigerator (not freezer).

• Teach patient how to monitor and record blood glucose level and, if indicated, urine glucose and ketone levels.

• Tell patient that dietary changes, activity, and stress can alter blood glucose level and insulin requirements.

• Instruct patient to wear medical identification stating that he is diabetic and takes insulin.

• Advise patient to have regular medical, vision, and dental exams.

• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs, tests, herbs, and behaviors mentioned above.