How To Treat Severe Pain In Anus Causing Difficulty To Defecate?

Hi, I have had severe anal pain for the last 4 months. ive been to docs 4 times, walk in cntr once all to no avail. i have shooting pains in my anus and its very painful to defecate? its really getting me down as there seems to be no resolution medically. im in pain as i write this.