Brief Answer:
Possible yeast infection

Detailed Answer:
Hello and welcome,

Based on your description, the location, and history, this is most likely a yeast overgrowth. We all have some yeast on our skin and genitals, and if conditions are right for it, it can overgrow and cause an irritated rash.

It's possible that he got it from sexual intercourse but also possible that his own microflora and conditions were right for this to happen.

I'd recommend the following:

1. Please get a topical anti-yeast cream (such as one containing Terconazole) from a drug store and apply as directed.

2. Avoid intercourse until it is fully cleared, at least 1 week.

3. He should keep the area dry and with good air exchange because of yeast like dark, damp, moist conditions. After showering, XXXXXXX dry and can dry additionally with a hand-held hair dryer on the lowest setting (to avoid getting it to inflame/burn the skin being too hot).

4. If he gets sweaty such as after exercise, wash off and change underwear.

5. Wear cotton boxers for maximum air circulation, dryness and coolness.

6. Avoid soaps and other products that have fragrances and other irritants.

Now the question is, should you be treated as well? If this is the first time he has had a rash, and you are symptom-free, you can wait and see if it reoccurs. If it does, both of you should be treated.

Sometimes a yeast infection in a man can happen in the presence of elevated blood sugars, so if that is at all a possibility, he should get a fasting blood glucose level checked.

Finally, if there is any risk of STDs, they can sometimes present like this, but what you are describing is more typical for yeast overgrowth.

I hope this information helps.
Please let me know if I can provide further information.

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