Hello and Welcome to ‘Ask A Doctor’ service. I have reviewed your query and here is my advice. Blisters on the genital area, in majority of cases, suggests sexually transmitted disease. It is better he consults a doctor and get evaluated. There are many possible causes for a genital rash, ranging from infections that are treatable to a sexually transmitted disease, allergies, and autoimmune disorders. Some of the most common causes of genital rashes are infections: 1. Jock itch is a fungal infection, or ringworm of the groin area. The rash is red, itchy, and scaly, and it may blister. 2. Molluscum contagiosum is a viral infection that affects the skin and presents as firm, isolated, round bumps. They may be itchy and inflamed. 3. Balanitis is an inflammation of the foreskin or the head of the penis that is usually caused by poor hygiene. It causes itchiness, redness, and a discharge. 4. Genital herpes (small, painful blisters filled with clear or straw-colored fluid) 5. Genital warts (flesh-colored spots that are raised or flat, and may look like the top of a cauliflower) 6. Chancroid (a small bump in the genitals, which becomes an ulcer within a day of its appearance) 7. Syphilis (small, painless open sore or ulcer [called a chancre] on the genitals) 8. Granuloma inguinale (small, beefy-red bumps appear on the genitals or around the anus) 9. Lymphogranuloma venereum (small painless sore on the male genitals) I suggest you always make sure he uses condoms before intercourse. Still there are chances that you may contract disease because of him. Thats why its very important that you make sure he gets treated at the earliest. Regards- Dr Sanjay Kini