Troglitazone
Troglitazone (Rezulin)
Troglitazone
(troh- GLIH-tah-zohn)
Pregnancy Category: B Rezulin (Rx)

Classification: Oral hypoglycemic

See Also: See also Hypoglycemic Agents.

Action/Kinetics: Lowers blood glucose by improving the target cell response to insulin without increasing pancreatic insulin secretion. Decreases hepatic gluconeogenesis and increases insulin-dependent glucose disposal in skeletal muscle and perhaps liver and adipose tissue. This effect may be due to a binding of the drug to nuclear receptors that regulate the transcription of a number of insulin responsive genes required for the control of glucose and lipid metabolism. Troglitazone is not an insulin secretagogue. Rapidly absorbed; maximum plasma levels: 2-3 hr. Steady-state plasma levels are reached in 3-5 days. Food increases the rate of absorption. t 1/2, elimination: 16-34 hr. Metabolized in the liver and excreted mainly in the feces.

Uses: With a sulfonylurea or insulin to improve control of type II diabetes. Alone as an adjunct to diet and exercise to lower blood glucose. Investigational: Use in the productive and metabolic consequences of polycystic ovary syndrome and essential hypertension with type II diabetes.

Contraindications: Lactation. Use for type I diabetes or for the treatment of diabetic ketoacidosis.

Special Concerns: Use with caution in those with liver disease and in those with CHF. Ovulation may resume in premenopausal anovulatory clients, leading to an increased risk of pregnancy. Safety and efficacy have not been determined in children.

Side Effects: GI: Nausea, diarrhea. CNS: Headache, dizziness. Metabolic: Hypoglycemia. Hematologic: Decreased hemoglobin, hematocrit, and white blood cell counts. Nose/throat: Rhinitis, pharyngitis. Miscelleaneous: Infection, pain, accidental injury, asthenia, back pain, UTI, peripheral edema, severe idiosyncratic hepatocellular injury (rare).

Laboratory Test Alterations: AST, ALT, both of which are reversible. Small changes in serum lipids.

Drug Interactions: Cholestyramine / Absorption of troglitazone effect Cyclosporine / Effect of cyclosporine due to breakdown by the liver HMG-CoA reductase inhibitors (antihyperlipidemics) / Effect of antihyperlipidemic due to breakdown by the liver Oral contraceptives containing ethinyl estradiol/norethindrone / Plasma levels of the hormones contraceptive effect Tacrolimus / &arrowdn;: Effect of tacrolimus due to breakdown by the liver Warfarin / Potentiation of effects of warfarin on INR

How Supplied: Tablets: 200 mg, 300 mg, 400 mg.

Dosage
?Tablets With insulin in type II diabetes mellitus.
Adults, initial: 200 mg daily while continuing the insulin dosage. If the response is inadequate, the dose of troglitazone may be increased after 2 to 4 weeks. Usual daily dose: 400 mg/day. Maximum daily dose: 600 mg/day. The insulin dose should be decreased by 10% to 25% when fasting plasma glucose levels decrease to less than 120 mg/dL in clients receiving both insulin and troglitazone.
With sulfonylureas in type II diabetes mellitus.
Adults, initial: 200 mg once daily. Continue the sulfonylurea dose. If response is inadequate, increase the dose of troglitazone at 2 to 4 weeks, not to exceed 600 mg/day. The sulfonylurea dose may need lowering to optimize therapy.
Monotherapy for type II diabetes mellitus.
For those not responding to 400 mg once daily, increase the dose to 600 mg after 1 month. For those not responding adequately to 600 mg after 1 month, consider alternative therapy.
Polycystic ovary syndrome.
Adults: 400 mg/day.