Half-Life of Etoricoxib 120mg
The elimination half-life of etoricoxib 120mg is approximately 20 hours, which enables once-daily dosing. 1
Pharmacokinetic Profile of Etoricoxib
- Etoricoxib is a selective COX-2 inhibitor with moderate absorption rate when administered orally, reaching maximum plasma concentration after approximately 1 hour 1
- The drug is extensively protein bound, primarily to plasma albumin, with an apparent volume of distribution of 120L in humans 1
- The area under the plasma concentration-time curve (AUC) increases proportionally with doses between 5mg and 120mg 1
- After administration of etoricoxib 120mg film-coated tablets, the mean maximum plasma concentration (Cmax) is approximately 3155.93 ng/mL 2
Metabolism and Elimination
- Etoricoxib undergoes biotransformation primarily via the cytochrome P450 (CYP) 3A4 isoenzyme 1
- The drug is eliminated following biotransformation to carboxylic acid and glucuronide metabolites 1
- These metabolites are excreted in both urine and feces, with very little of the drug (<1%) being eliminated unchanged in urine 1
- The long half-life of approximately 20 hours supports the once-daily dosing regimen commonly used in clinical practice 3
Clinical Implications of Half-Life
- The extended half-life of etoricoxib (approximately 20 hours) provides sustained analgesic effects, with duration of action exceeding 24 hours for doses of 120mg and higher 4
- When considering perioperative management, medications with longer half-lives like etoricoxib (20 hours) require earlier discontinuation compared to NSAIDs with shorter half-lives like ibuprofen (2-6 hours) 5
- For high bleeding risk procedures, the timing of discontinuation should account for 4-5 elimination half-lives to ensure minimal residual effect at the time of surgery 6
Comparison with Other NSAIDs
- Etoricoxib has a significantly longer half-life (approximately 20 hours) compared to traditional NSAIDs like ibuprofen (2-6 hours) 5, 1
- The half-life of etoricoxib is similar to other long half-life NSAIDs such as piroxicam 5
- This extended half-life contributes to etoricoxib's prolonged analgesic effect, with studies showing pain relief lasting >24 hours after a single 120mg dose 4
Special Populations
- Plasma concentrations of etoricoxib appear not to be significantly different in patients with chronic renal insufficiency compared to those with normal renal function 1
- However, patients with moderate hepatic impairment show approximately 40% increase in AUC compared to healthy subjects 1
- When calculating appropriate timing for discontinuation before procedures, the half-life of approximately 20 hours should be considered, with potential adjustments for patients with hepatic impairment 7, 1