Sulfonylureas pharmacokinetics

Pharmacokinetics All sulfonylureas are strongly bound to plasma proteins, primarily albumin. 

Mechanism of Action Afirst-generation sulfonylurea that promotes release of insulin from beta cells of pancreas. Therapeutic Effect Lowers blood glucose concentration. Pharmacokinetics Rapidly absorbed from the gastrointestinal (Gl) tract. Protein binding 60%-90%. Extensively metabolized in liver. Excreted primarily in urine. Removed by hemodialysis. Half-life 30-42 hr. 

Schulz E, Koch K, Schmidt FH. [Potentiation of the hypoglycemic effect of sulfonylurea derivatives by drugs. II. Pharmacokinetics and metabolism of glibenclamide (HB 419) in presence of phenylbutazone.] Eur J Clin Pharmacol 1971 4(l) 32-7. 

ABSORPTION, FATE, AND EXCRETION The sulfonylureas have similar spectra of activities thus, their pharmacokinetics are their most distinctive characteristics. All are effectively absorbed from the gastrointestinal tract, although food and hyperglycemia can reduce the absorption. In view of the time required for absorption, sulfonylureas with short half-lives may be more effective when given 30 minutes before eating. Sulfonylureas in plasma are largely (90-99%) bound to protein, especially albumin. The volumes of distribution of most of the sulfonylureas are about 0.2 L/kg. 

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