Table 2: Effect of essential oil (EO) of Citrus limon, morphine (MOR) and aspirin on formalin-induced pain.

TreatmentDose (mg/kg)No. of licks (s)
0–5 min15–30 min
Score of pain*% inhibitionScore of pain*% inhibition

Vehicle ±
EO50 a11 11
EO100 a,b36 a,b85
EO150 a,b,c81 a,b,c92
MOR5 a95 a94
Aspirin200 a,d27 a,d92

per group.
*Values represent mean ± SEM.
a , significantly different from control, b , significantly different from EO 50 group, c , significantly different from EO 100 group, d , significantly different from MOR group. One-way ANOVA followed by Dunnett’s test was applied to all data.