Hello,

Thanks for writing in.

This may be frictional dermatitis. The to and from motion over the penile skin sometimes leads to irritation of the skin.
Emollients like Vaseline help in reducing this irritation. If the irritation is too much and if the skin gets red despite using vaseline, then you may try applying a mild hydrocortisone cream. This usually gives an immediate relief.

If you are using Condoms, it may be latex allergy. In the case you have to see a dermatologist personally and get your yourself patch-tested for latex allergy.

I hope I have answered your query.
Please do not hesitate to ask me any further questions, should you have them

Thanks

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