Penis-Related Symptoms That Could Indicate an STI

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Sexually transmitted infections (STIs) are diseases passed along through sexual contact. While some are harmless, others can cause problems ranging from discomfort to cancer to AIDS.

Symptoms of a Sexually Transmitted Infection in Men

STIs often cause symptoms that affect the penis or groin area. If you're concerned by something you've noticed on your body, you should consult with a doctor. In the meantime, however, look at this list of six possible symptoms that affect the penis. If any of them sound familiar, it may indicate that you've contracted an STI.

  • Discharge from the Penis: A thick white, yellow, or green discharge from the tip of the penis may be a sign of gonorrhea, especially if you also experience pain in the urethra or pain with urination.
  • Single Sore on the Penis: In primary syphilis, a hard, painless, dime-sized sore (sometimes compared to a button) appears on the penis. This is usually accompanied by a swelling of the lymph nodes in the groin.
  • Penile Pain or Discomfort: Pain, itchiness, or discomfort—often associated with urination—may be a sign of a sexually transmitted infection.
  • Painful Blisters or Scabs on the Penis: A cluster of painful or itchy red spots and small blisters on the penis may be a sign of genital herpes. Typically, the pain or itching comes first, followed a day or two later by the appearance of blisters. Herpes sores may also appear on the scrotum, thighs, and buttocks.
  • Brown Flecks on the Hair Around the Penis: If you find tiny grey-brown eggs on the shafts of your pubic hair, this may be a sign of infestation by pubic lice (also called "crabs").
  • Red Bumps on the Penis and Scrotum: A scabies infestation will cause red, itchy bumps and nodules, which typically appear in lines. Usually, similar lesions will also pop up elsewhere on your body.

What to Do If You Think You Have an STI

If you are experiencing any of these symptoms, call your doctor right away and ask for an appointment so you can be tested and, in the event of a positive diagnosis, receive the appropriate treatment.

If a diagnosis is confirmed, be sure to alert any sexual partners. They may also need to be tested and treated. And be sure to engage in safe sex practices going forward, if you aren't already. Contraceptive methods such as condoms, in particular, can be incredibly effective when it comes to protecting against STIs.

Sexually Transmitted Infections Often Have Other Symptoms

You should also know that many STIs have physical symptoms that manifest elsewhere on the body. If you notice anything out of the ordinary, even if it's not on your genitals, it could still be an indication of an STI. If you're sexually active, familiarize yourself with all of the possible signs of the most common STIs.

Knowledge is power and the more you know, the better able you'll be to protect yourself and your partners.

Penis Infections Are Not Necessarily STIs

Sometimes penis infections happen for other reasons too. You may have a yeast infection, a urinary tract infection, balanitis, or even penile cancer.

Be sure to see your doctor if you have any unusual symptoms.

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Article Sources

  1. STD Facts - Gonorrhea. Centers for Disease Control and Prevention.

  2. STD Facts - Syphilis. Centers for Disease Control and Prevention.

  3. Richens J. Main presentations of sexually transmitted infections in men. BMJ. 2004;328(7450):1251-3.


  4. STD Facts - Genital Herpes. Centers for Disease Control and Prevention.

  5. Fader BM. The diagnosis and treatment of scabies and pubic lice. Primary Care Update for OB/GYNS. Published March 1, 1999.


  6. Mccarthy JS, Kemp DJ, Walton SF, Currie BJ. Scabies: more than just an irritation. Postgrad Med J. 2004;80(945):382-7.


  7. Condom Effectiveness | CDC. Centers for Disease Control and Prevention.

  8. Buechner SA. Common skin disorders of the penis. BJU Int. 2002;90(5):498-506.


Additional Reading

  • Barry, M, Kauffman, CL, Wilson, BB, Rozen E, Rosh AJ. Scabies. Medscape.

  • Chandrasekar, PH. Syphilis. Medscape.

  • Wong, B. Gonorrhea. Medscape.