Hello, You have a pimple like bump on the glans and underside of the shaft. Pimples go away on their own. Take care of your hygiene. Shower regularly and avoid rubbing or touching the affected region. Minimize activities that induce sweating. Avoid humid environments. You can apply ointment Tretinoin cream or Soframycin cream. You can apply hydrocortisone cream on the affected area if itchy. Get STD tests done, if genital warts or herpes are detected. Herpes is treated with antivirals like acyclovir and warts with Imiquimod (Aldara, Zyclara) or trichloroacetic acid, etc. Surgery includes laser therapy, cryotherapy or electrocautery, etc. Milia don’t need treatment because they’re not harmful. Cryotherapy is commonly used to freeze milia. Practice safe sex to avoid rashes caused by STIs. Eat a balanced diet and regularly exercise to keep the immune system strong. Allergic reactions can be prevented by avoiding food, dust, pollution, animal dander, perfumed body products that trigger the allergies. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Nupur K., General & Family Physician