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Date of last update: 10/12/2017.

Forum Name: Sexually Transmitted Diseases

Question: Small red bumps on underside of penis.

 soccerbloke - Fri Sep 19, 2008 3:27 pm

This is the second time I have had this painless, itchless rash on the underside of my penis. They are pin-sized, red, raised bumps but they do not blister or pop or anything and eventually in a few days they just get dry and scab over and then they're gone. I have regular unprotected sex with my girlfriend (who has been tested and is on the pill). I have had blood work done recently when I was in the hospital for a viral infection and everything came up fine. I think that this could be a soap allergy as the last time I got this I switched soap to one with exfoliating beads. Any advice? I can send a picture if need be.
 Dr. Safaa Mahmoud - Mon Oct 27, 2008 3:12 pm

User avatar Hello,

These lesions are likely to be due to dermatitis.
Dermatitis are caused by infections, allergies, and irritants (such as soaps, certain creams).

- Infections like:
Herpes simplex usually presents with small, very painful blisters that burst into then scab and heal in about 3 weeks.

Friction and fungus cause red patches that are also itchy. Obese and active people are more susceptible.

- Dermatitis can occur also due to contact with an allergen or irritant like soap, creams, synthetic cloth, or after vigorous sexual intercourse or masturbation.

Direct clinical examination is essential, so I would advise you to follow up with your doctor for proper management.
Please keep us updated.
Best regards.

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