<s>[INST] My son is 20 months old he had a pus filled blister on the tip of his penis along with redness so i took him to the doctor then i notice he had blueness so i took him to the doctor again now that he s home again i notice it s red and now purple i m worried he seems to urinate normally but every time i have to change his diaper and when I want to check his penis he doesn t want me to touch it as if it hurts him he was circumsized at birth [/INST] Hi, I have gone through your question and I understand your concerns but this is probably due to an infection which might require an antibiotic either local or systemic. Please send a photo of the lesion to be able to help you further. Hope I have answered your query. Let me know if I can assist you further. Regards, Dr. Salah Saad Shoman, Internal Medicine Specialist </s>