Exib Mechanism of Action

Pharmacology: Pharmacodynamics: Etoricoxib is a non-steroidal anti-inflammatory drug (NSAID), selective cyclooxygenase-2 (COX-2) inhibitor, COX-2 is the isoform of cyclooxygenase that has been shown to be induced by pro-inflammatory stimuli and has been postulated to be primarily responsible for the synthesis of prostanoid mediators of pain, inflammation, and fever. Etoricoxib did not inhibit gastric prostaglandin synthesis and had no effect on platelet function.
Pharmacokinetics: Absorption: Orally administered etoricoxib is well absorbed. The absolute bioavailability is approximately 100%. The peak plasma concentration was observed at approximately 1 hour (T_max) after administration to fasted adults. Dosing with food (a high-fat meal) had no effect on the extent of absorption. The rate of absorption was affected, resulting in a 36% decrease in C_max and an increase in T_max by 2 hours.
Distribution: Etoricoxib is approximately 92% bound to human plasma protein. The volume of distribution at steady state was approximately 120 L.
Biotransformation: Etoricoxib is extensively metabolized with less than 1% of a dose recovered in urine as the parent drug. The major route of metabolism to form the 6'-hydroxymethyl derivative is catalyzed by CYP enzymes. CYP3A4 appears to contribute to the metabolism of etoricoxib.
Elimination: It occurs almost exclusively through metabolism followed by renal excretion, 70% in urine and 20% in faeces. Less than 2% was recovered as unchanged drug. The half-life of etoricoxib is approximately 22 hours.