Glyburide is a sulfa drug used in the management of blood sugar levels in people suffering from diabetes mellitus type II. Although managing diet and exercise are the most effective means of managing this condition, glyburide can complement these approaches to diabetes management by helping to lower blood sugar levels. This medication is sometimes used to reduce the severity of injury caused by brain swelling in stroke patients as well. When calculating the appropriate glyburide dose to administer initially, it is important to factor in the patient's age, kidney health, and liver health as well as the form of the medication to be used. Patients switched to glyburide from another, longer-acting blood sugar lowering medication should be given reduced doses and be closely monitored for symptoms of hypoglycemia for the first week of use.
When administering this medication to an adult with diabetes mellitus type II, the initial glyburide dose should be 2.5 mg given with breakfast in the morning. When using the micronized form, the initial dose should be just 1.5 mg. A maintenance dose between 1.25 and 20 mg of conventional glyburide or 0.75 to 12 mg of micronized glyburide can be given in one or two divided doses throughout the day. No more than 20 mg of conventional or 12 mg of micronized glyburide should be used in a 24 hour period. The initial dose for patients 65 years of age or older may be reduced to as little as half that of the standard glyburide dose, although the standard dose may still be given in serious cases. Increases in glyburide dose may be considered every seven days in increments of 2.5 mg of the conventional form and 1.5 mg of the micronized form.
In patients suffering from diminished kidney function, a dosage adjustment may be necessary. The initial glyburide dose given should be half of the standard adult dose given once daily. Incorporating maintenance doses into the patient's treatment regimen should be done with care. Since the medication is not removed by dialysis, supplemental doses in patients undergoing this procedure are not required. The same dosage adjustment recommendations should be followed when administering glyburide to patients with lowered liver function.
Other risks of glyburide include some serious and potentially fatal drug interactions, particularly with the medications gatifloxacin and bosentan. Alternative drugs should be used, as the concomitant use of gatifloxacin can cause hypoglycemic coma, while bosentan can produce severe liver damage. In addition to the risk of hypoglycemia in overdose, some patients also develop cholestatic jaundice, a condition found more commonly in patients taking glyburide in combination with the anti-diabetic medication metformin.