Results: The group was used "Hoang ky que chi ngu vat thang" had a statistically significant greater time of pain occurrence (p < 0.05) compared to the control group and similar to the reference group (Aspegic); the number of writhing pain, during 25 minutes after acetic acid injection, in both groups with dose 1 and dose 2 were statistically significantly lower (p < 0.01), equivalent to the reference group (Aspegic).