Suggest Medication For A Blackhead Filled With Pus

Hi, may I answer your health queries right now ? Please type your query here...I had a hard blackhead that kept returning that was located directly in the middle of my back on my spine. I had a doctor remove it once on a routine visit. Them I have gotten my husband to remove it a couple of time. A few days ago I had this soft squichy spot where the black head usually is and it popped in the shower with a lot of pus coming out of it followed by blood. If seemed to fill back up within a couple of days and then I feel it again and it pops with the pus and small amount of blood. What could this be?