Figure 5.

Repeated acetaminophen injections. Male mice were assigned to receive 4 daily injections of either acetaminophen (IP APAP, 300 mg/kg) or vehicle (IP, 10 mL/kg) (days 1–4). On day 5, all animals received IP APAP (300 mg/kg) 30 minutes before intraplantar formalin. (A) Flinch count (mean ± SEM) for mice following intraplantar formalin delivered at time 0. (B) Scattergram for cumulative flinching count (AUC: median/quartiles) for phase 1 (0–10 minutes) and phase 2 (11–45 minutes). AUC analysis for phase 1 and phase 2 flinching between the 2 treatment groups was performed nonparametrically with a rank-sum test; ns: nonsignificant; P > 0.05. APAP, acetaminophen; AUC, area under the curve; IP, intraperitoneal.