Impetigo is a contagious skin infection, of which there are 2 different types: Bullous and Non-Bullous, which have varying symptoms to each other.
70% of cases are Non-bullous. Its main symptom is the presence of honey-coloured crusts of skin on the face and is caused by is caused by Staphylococcus aureus or Streptococcus pyogenes.
30% of cases are Bullous Impetigo, whose main symptom is the presence of large blisters containing serous fluid, on the face. It is caused by S. aureus.
There is a variety of different antibiotics that can be used to treat impetigo including topical antibiotics such as mupirocin, retapamulin, and fusidic acid.
For the Bullous impetigo, oral antibiotic therapy is generally the chosen kind of therapy. "Amoxicillin/clavulanate, dicloxacillin, cephalexin, clindamycin, doxycycline,minocycline, trimethoprim/sulfamethoxazole, and macrolides are options, but penicillin is not."
Impetigo: diagnosis and treatment. (Hartman-Adams H, Banvard C, Juckett G. 2014: 229-235)