Hello, Red blotch on the penis head is indicative of fungal or bacterial infection that grow easily in warm, moist areas like under the foreskin. It is not STD, it can be balanitis that causes red spots, itching or even swelling / inflammation. It is commonly caused due to poor hygiene. Take care of your hygiene. Take regular bath, keep your private organs clean. Change clothes regularly, avoid wearing clothes on which you have sweated. Wear cotton clothes that are loose fitting. Avoid the use of strong soaps that may trigger allergic reaction. You can apply a thin layer of Hydrocortisone cream to ease discomfort. If you have such symptoms repeatedly then circumcision is the best answer. In case of fungal infection, you can take an oral course of Fluconazole. Ointment Clotrimazole is also equally effective. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Nupur K., General & Family Physician