Objective: To observe the efficacy of Peitu Zhixie decoction combined with trimebutine maleate on irritable bowel syndrome with diarrhea (IBS-D) of spleen and stomach deficiency type and investigate its effect on calcitonin gene related peptide (CGRP) and aquaporins-8 (AQP-8). Method: One hundred and ten patients with IBS-D were randomly divided into control group and observation (55 patients for each group) by random number table. Patients in control group orally received trimebutine maleate (2 granules/time

tid). Based on the treatment of control group

the patients in observation group were given with additional Peitu Zhixie decoction (1 dose/d

bid). The treatment course was 6 weeks for both groups. Main symptom scores were evaluated pre-post treatment. IBS life scale was used to assess quality of life for all cases. Serum CGRP and AQP-8 levels were detected in both groups before and after treatment. Result: The total effective rate was 96.36% in observation group

superior to 81.88% in control group (P<0.05). After treatment

scores for abdominal distension

abdominal pain

diarrhea

and stool shape in observation group were significantly higher than those in control group (P<0.01). Scores of mental state

emotional state

diet influence

sleep status

daily exercise

energy change

daily social and work in observation group were significantly higher than those in control group after treatment (P<0.05). After treatment

serum CGRP level in observation group was significantly lower than that in control group

while AQP-8 level was significantly higher than that in control group

with statistically significant difference (P<0.05). Conclusion: Peitu Zhixie decoction combined with trimebutine maleate for IBS-D of spleen and stomach deficiency syndrome can reduce clinical symptoms

improve quality of life

significantly decrease serum CGRP level and increase AQP-8 level.