| Placebo (pg/mL) | Meloxicam 0.03% (pg/mL) | Diclofenac 0.1% (pg/mL) | |
| Basal (SD) | 21 (14) | 21 (14) | 21 (14) |
| Croton oil | ⩾1000 | ⩾1000 | ⩾1000 |
| 4 h (SD) | ⩾1000 | ⩾1000 | 32 (11)* |
| 24 h (SD) | ⩾1000 | 120 (39)* | 12 (3)* |
| 72 h (SD) | ⩾1000 | 35 (4)* | ⩾1000 |
| 144 h (SD) | 33 (11) | 27 (6) | ⩾1000* |