Strep throat and tonsillitis can cause a bad sore throat. However, when an abscess develops, the sore throat can truly be terrible and unresponsive to antibiotics. Throat abscess comes in two different flavor. The most common is the peritonsillar abscess . More rarely, a retropharyngeal abscess can develop. The pain can be so bad that these patients often go to the ER. Such throat abscesses often require surgical incision and drainage in order to resolve.