My 18 year old son had a blister looking thing that filled up with yellow puss suddenly on Sunday and it was red around the outside.  I took him to Urgent care, they pushed the puss out and the blister went flat, the redness also cleared up.  They gave him a topical ointment to use.  Today the blister filled up again, but not as much.  There is a little yellow puss but not much. No pain, no redness, no fever.  I am concerned that it filled up again.  Urgent care did not think it was a staph infection.  My son did have a heating pad on his arm about an hour before the blister appeared but he said the pad was not that hot as to burn him.  The heating pad is a clay filled pad.  Since he has only used the topical ointment for 1 day I was going to have him continue the ointment another day or two, keep it covered and if it doesn't look better I will take him to his GP, do you think its wise to give the medication a few days to heal the area or should I be concerned and go to GP ASAP?
                                                        
                                                     
                                                    
                                                        
                                                            
                                                            
                                                            
                                                                posted on
                                                            
                                                                Sat, 21 Dec 2013 
                                                            
                                                            
                                                            
                                                            
                                                                
                                                                    
                                                                    
                                                                    Sat, 21 Dec 2013
                                                                    
                                                                    
  Answered on 
                                                                 
                                                                
                                                                    
                                                                    
                                                                    Mon, 23 Dec 2013
                                                                    
                                                                    
  Last reviewed on