Objective To observe the clinical therapeutic effect of Shudu Bushen Recipe （Recipe to strengthen the spine and reinforce the kidney） on ankylosing spondylitis at active stage.Methods Totally 165 patients with ankylosing spondylitis at active stage were randomly divided into a treatment group （85 cases） and a control group （80 cases）.Both groups were treated with Sulfasalazine and Aceclofenac

and the trentment group was given Shudu Bushen Recipe additionally.Six-month treatment was one course.The clinical changes such as morning stiffness

joint pain and function

erythrocyte sedimentation rate （ESR）

C-reactive protein （CRP）

immunoglobulin （Ig）

X-ray of sacroiliac joint

and adverse reaction were observed.Results In the treatment group

the total effective rate was 94.12%

superior to that in the control group （76.25%）

with a significant difference （P<0.05）.Compared with that before treatment

only the occiput-wall distance of the control group remained unchanged

other clinical and laboratory indices of both groups improved （P<0.05 or P<0.01）.The duration of morning stiffness

the number of peripheral joint pain

ESR

CRP of the treatment group after treatment were significantly different from those of the control group （P <0.05 or P<0.01）.There was no significant difference in the changes of X-ray of sacroiliac joint of both groups （P>0.05）.The adverse reaction occurred in the treatment group was less than that of the control group （P<0.05）.Conclusion To treat ankylosing spondylitis at active stage

the treatment with Shudu Bushen Recipe in combination with Sulfasalazine and Aceclofenac was more effective and with less adverse reaction than treatment with western drugs.