At this point, lack of compliance is assumed to have been excluded. A link with an interested microbiologist is necessary since Propionibacterium acnes are not easy to grow. Swabs must be taken from  the nose and the lesions to exclude Gram-negative folliculitis. Anaerobic samples also need to be processed for Propionibacterium acnes and their sensitivities ascertained.

 

  Working from these results the physician could then either treat the Gram-negative folliculitis  or, if the P.  acnes are resistant , use an appropriate antibiotic  therapy.  If the microbiologist fails to grow any Gram-negative bacteria and if the P. acnes are still sensitive then it is quite likely that the reason for the failure is inadequate  levels of the drug reaching the pilosebaceous system.

 

  One therapeutic policy is then to double the dose of the antibiotic or to use one of the brandnamed antibiotics such as minocycline or doxycyline. The addition of a nonsteroidal anti-inflammatory,  such  as  ibuprofen 400 mg bds could be  tried in conjunction with the antibiotics for twelve weeks.