glipizide

glipizide

(glip' i zide)

Glucotrol, Glucotrol XL

Pregnancy Category C

Drug classes

Antidiabetic

Sulfonylurea (second generation)

Therapeutic actions

Stimulates insulin release from functioning beta cells in the pancreas; may improve binding between insulin and insulin receptors or increase the number of insulin receptors; more potent in effect than first-generation sulfonylureas.

Indications

·        Adjunct to diet and exercise to lower blood glucose with type 2 (non–insulin-dependent) diabetes mellitus

·        Adjunct to insulin therapy in the stabilization of certain cases of type 1 (insulin-dependent) diabetes, reducing the insulin requirement and decreasing the chance of hypoglycemic reactions

Contraindications and cautions

·        Contraindicated with allergy to sulfonylureas; diabetes with ketoacidosis, sole therapy of type 1 diabetes or diabetes complicated by pregnancy, diabetes complicated by fever, severe infections, severe trauma, major surgery, ketosis, acidosis, coma (insulin is indicated); type 1 diabetes, serious hepatic impairment, serious renal impairment.

·        Use cautiously with uremia, thyroid or endocrine impairment, glycosuria, hyperglycemia associated with primary renal disease; labor and delivery (if glipizideis used during pregnancy, discontinue drug at least 1 mo before delivery); lactation; pregnancy.

Available forms

Tablets—5, 10 mg; ER tablets—2.5, 5, 10 mg

Dosages

Give approximately 30 min before breakfast to achieve greatest reduction in postprandial hyperglycemia.

ADULTS

·        Initial therapy: 5 mg PO before breakfast. Adjust dosage in increments of 2.5–5 mg as determined by blood glucose response. At least several days should elapse between adjustments. Maximum once-daily dose should not exceed 15 mg; above 15 mg, divide dose, and administer before meals. Do not exceed 40 mg/day. ER tablets: 5 mg/day. Adjust dosage in 5-mg increments every 3 mo; maximum dose—20 mg/day.

·        Maintenance therapy: Total daily doses above 15 mg PO should be divided; total daily doses above 30 mg are given in divided doses bid.

·        Extended release: 5 mg/day with breakfast, may be increased to 10 mg/day after 3 mo if indicated.

PEDIATRIC PATIENTS

Safety and efficacy not established.

GERIATRIC PATIENTS

Geriatric patients tend to be more sensitive to the drug. Start with initial dose of 2.5 mg/day PO. Monitor for 24 hr and gradually increase dose after several days as needed.

Pharmacokinetics

Route	Onset	Peak	Duration
Oral	1–1.5 hr	1–3 hr	10–24 hr

Metabolism: Hepatic; T_1/2: 2–4 hr

Distribution: Crosses placenta; enters breast milk

Excretion: Bile, urine

Adverse effects

·        CNS: Drowsiness, asthenia, nervousness, tremor, insomnia, tinnitus, fatigue

·        CV: Increased risk of CV mortality

·        Endocrine: Hypoglycemia, SIADH

·        GI: Anorexia, nausea, vomiting, epigastric discomfort, heartburn, diarrhea

·        Hematologic: Leukopenia, thrombocytopenia, anemia

·        Hypersensitivity: Allergic skin reactions, eczema, pruritus, erythema, urticaria, photosensitivity, fever, eosinophilia, jaundice

·        Other: Weight gain

Interactions

Drug-drug

·        Increased risk of hypoglycemia with sulfonamides, chloramphenicol, oxyphenbutazone, phenylbutazone, salicylates, clofibrate

·        Decreased effectiveness of glipizide and diazoxide if taken concurrently

·        Increased risk of hyperglycemia with rifampin, thiazides

·        Risk of hypoglycemia and hyperglycemia with ethanol; "disulfiram reaction" also has been reported

Drug-alternative therapy

·        Increased risk of hypoglycemia if taken with juniper berries, ginseng, garlic, fenugreek, coriander, dandelion root, celery

Nursing considerations

Assessment

·        History: Allergy to sulfonylureas; diabetes with complications; type 1 diabetes, serious hepatic or renal impairment, uremia, thyroid or endocrine impairment,glycosuria, hyperglycemia associated with primary renal disease; pregnancy

·        Physical: Skin color, lesions; T; orientation, reflexes, peripheral sensation; R, adventitious sounds; liver evaluation, bowel sounds; urinalysis, BUN, serumcreatinine, LFTs, blood glucose, CBC

Interventions

·        Give drug 30 min before breakfast; if severe GI upset occurs or more than 15 mg/day is required, dose may be divided and given before meals.

·        Monitor urine or serum glucose levels frequently to determine drug effectiveness and dosage.

·        WARNING: Transfer to insulin therapy during periods of high stress (eg, infections, surgery, trauma).

·        WARNING: Use IV glucose if severe hypoglycemia occurs as a result of overdose.

Teaching points

·        Take this drug 30 minutes before breakfast for best results.

·        Do not discontinue this drug without consulting your health care provider.

·        Monitor urine or blood for glucose and ketones.

·        Do not use this drug during pregnancy; consult health care provider.

·        Avoid alcohol while using this drug.

·        Report fever, sore throat, unusual bleeding or bruising, rash, dark urine, light-colored stools, hypoglycemic or hyperglycemic reactions.

Adverse effects in Italic are most common; those in Bold are life-threatening.