Thanks for your query and a clear picture with the color stick to understand the inflammation.
This is called balanoposthitis. and can be due to humidity or can be due to STD if you had unprotected sexual interaction.
Your providing a proper and detailed history would have helped me.
Anyways the treatment remains similar and I would like to give you some guidelines.
Clean the area only with plain water, do not use soap.
You may apply Metronidazole ointment or liquid povidone iodine and nothing else.
A course of oral antibiotic and metronidazole helps to solve the issue. (you will need a prescription of a Doctor) and may be the STD panel tests at an appropriate time.
Hope this helps you.
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