OBJECTIVE: To compare the clinical efficacy of penehyclidine hydrochloride and phloroglucinol in the treatment of primary dysmenorrhea. METHODS: Totally 120 patients with primary dysmenorrhea admitted into Chongqing Emergency Medical Center from Jan. 2016 to Dec. 2018 were extracted to be divided into the observation group and the control group via the random number table

with 60 cases in each group. The observation group was administrated with intramuscular injection of 1 mg penehyclidine hydrochloride

while the control group was given intramuscular injection of 80 mg phloroglucinol. Visual analogue scale（ VAS） score

oneset time

clinical efficacy and adverse drug reactions of two groups were observed. RESULTS: Before treatment

the difference in VAS score between two groups was not statistically significant（ P>0. 05）. After administration of 15 min

the VAS score of the observation group was significantly lower than that in the control group

the onset time of the observation group was significantly shorter than that in the control group

and the differences were statistically significant（ P<0. 05）. After administration of 30 and 60 min

the difference in VAS score between two groups was not statistically significant（ P>0. 05）. There was no statistically significant difference in significant efficiency

effective rate and total effective rate between two groups（ P>0. 05）. The incidence of adverse drug reactions in the observation group was 13. 3%（ 8/60）

significantly higher than that in the control group 1. 7%（ 1/60）

and the difference was statistically significant（ P < 0. 05）.CONCLUSIONS: Penehyclidine hydrochloride and phloroglucinol are safe and effective in the treatment of primary dysmenorrhea. The onset time of penehyclidine hydrochloride is shorter than that of phloroglucinol

while the incidence of adverse drug reactions of phloroglucinol is lower than that of penehyclidine hydrochloride.