Brief Answer:
Need to rule out other causes as well

Detailed Answer:
Hi,

Thanks for consulting HealthCareMagic!

"Ring like" rash may point towards many things like fungal infections, rash due to friction and trauma, sexually transmitted diseases and as you suspect very rarely because of allergy to lubricants.

If the rash appears after the use of lubricant and goes away when stopped, it may point towards it's allergy. But as these kind of allergies wont present classically as
"Ring like" rash, other possibilities such as the ones I mentioned above have to be ruled out based on physical examination and few tests.

Hope I have answered your query. Let me know if I can assist you further. If you are satisfied please proceed with closing and rating this answer.

Wish you a good health!

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