Version August 2025
| COX-2 selectivity* | Gastric IC50 (micromolar)¶ | |
| NSAIDs | ||
| Ketoprofen | 0.1 | 0.08 |
| Ibuprofen | 0.6 | 0.70 |
| Indomethacin | 0.7 | 0.85 |
| Naproxen | 1.0 | 0.52 |
| Piroxicam | 1.3 | 0.87 |
| Ketorolac | 1.5 | 0.33 |
| Nabumetone | 1.6 | 0.48 |
| Etodolac | 7.9 | 3.20 |
| Celecoxib | 9.2 | 11.14 |
| Mefenamic acid | 12.1 | 0.70 |
| Nimesulide (not available in United States) | 58.3 | 1.49 |
| Other analgesics | ||
| Aspirin (acetylsalicylic acid) | 0.3 | 0.03 |
| Salsalate (salicylsalicylic acid) | ≥2.8 | >100 |
| Acetaminophen | 4.0 | >100 |
6MNA: 6-methoxy-2-naphthylacetic acid; COX: cyclooxygenase; IC50: half-maximal inhibitory concentration; PG: prostaglandin.
* In whole blood assays in man. A number ≅1 indicates COX nonselectivity, while numbers much >1 indicate COX-2 selectivity. Values for nabumetone are for its active metabolite, 6MNA.
¶ Concentration of drug that inhibits human gastric mucosal COX activity by 50% and thus gastric mucosal PG production by 50%. The lower the IC50, the more potent the inhibition of gastric COX activity for a given drug.