ONE SPECIFIC guy gets rash immediately after he sleeps with me

[mooneyes]

Hi all-

I've been on and off with one guy for a couple years. The past couple times we've been on, he's gotten a rash a day or two after he's slept with me. This hasn't happened with any of my other partners, ever, and I don't show any symptoms. When he got it checked the practitioner told him it wasn't herpes as we thought, but that she couldn't identify it. I am DFAB and he's DMAB.
Neither of us has any idea what is happening and we're very stressed and confused. The bumps are red and itchy and are generally showing up under his pubes, none on his penis. They haven't ever burst, they just disappear after a few days. What's happening? Is it an allergy to my lipgloss or an unfortunate pH problem? Is it an sti?

Thank you for your help

[Siân]

Hi mooneyes,

I'm glad you have been to see a practitioner already about this, and really healthcare providers are the best people to answer this kind of question. If you haven't already both had a full STI screening we always recommend regular checkups so this seems like a good opportunity. If they come back negative I would suggest seeing another practitioner or asking the one he has seen before for next steps/recommendations. Does that make sense?

[Heather]

I would add that because this sounds like it could very possibly be some kind of allergic reaction, maybe the next time see what happens if you basically are together as clean and free of any products as possible: so, no lipgloss, no body lotions or fragrances, no makeup, etc. Just a clean body, face and hair with as few products as possible. Then, if it turns out he doesn't get these bumps, you can slowly add one thing back at a time to see which thing made them happen, make sense?

That said, it can also be a simple heat rash, which can happen just from all the heat and pressure sex with another person often involves. But I agree with Sian: being sure you are both up to date with all your STI screenings is an important start regardless (and would be even if this were not happening).