Each Paroxib IV/IM Injection contains Parecoxib Sodium INN equivalent to Parecoxib 40 mg. Parecoxib is a prodrug of valdecoxib. This is a selective COX-2 inhibitor.
Valdecoxib's affinity for COX-2 versus COX-1 is 90 times greater than celecoxib and 34,000 times greater than ketorolac.