Acne on the flank, in TCM, belongs to the liver meridian depressed heat, stagnant fire, stasis poison, which can be accompanied by bitter fullness in the chest, dry mouth, dizziness, red eyes, red tongue with yellow coating, and string veins. Clinical treatment requires draining the fire and toxin of the liver and gallbladder, which can be done by taking oral gentian diarrhea soft capsule, and also by applying Chinese medicine fire acupuncture for quick puncture to draining the fire and toxin. In terms of topical medication, gentian ointment or Qingpeng ointment can be applied. For western medicine treatment, benzoyl peroxide gel can be applied, while minocycline hydrochloride capsules or doxycycline capsules can be taken orally.