I have an abscess on my bum. it is on the outside, right above the coccyx.

Doctor can evaluate: Some people are born with a pilonidal cyst at the top of the butt crack. Sometimes the cyst gets infected and needs treatment, such as drainage or antibiotics. A skilled surgeon can remove the cyst after treatment. If not removed, the problem tends to recur. One can see his primary care doctor to get a diagnosis as to what his problem truly is, and then start whatever treatment process is needed.