I have a white gold set of rings that are rhodium plated. I had the same problem, and was trying to find out what to do. I would take them off, clean them good, put triple antibiotic on my finger until it seemed to heal, then put the rings back on and the same thing would happen (a reddish rash under where the rings touched my skin). I have a ring on my right hand that this did not happen with, and I noticed that the rash was confined to the area where the diamonds were (so bacteria could have accumulated there due to moisture and caused a form of athletes foot). To test this possibility, I took off my rings (cleaned them and put them on the dresser to dry all night), put Lotrimin (athletes foot medication) around my ring finger, and put a band aid on it overnight. The next morning the rash was gone, I put my clean and dry rings, and haven't had a problem since. I hope people read this and I hope it helps.
I have the exact same problem happening on my middle finger on my right hand. It has nothing to do with rings since I don't wear jewelry on my right hand period. It starts out super dry at first, then it gets red, itchy, irritated (with the tiny little blisters that seem to have water or clear liquid when popped or scratched), and finally begin to dry out and "heal" for a day or two. I have been under an intense amount of stress the past six months (which is when they began). It fist started on my right wrist, went away for months, and came back on my finger and has been there for the past four or five months. I've used creams that a doctor provided (something called "Locoid", but it only helps relieve the itching.
Please let me know if you found a cure or if you have any idea what this could be!
This could indeed be a fungal infection and needs to be evaluated by a doctor. Applying alcohol is not exactly any treatment and your doctor would be able to clarify further on this.
have you had other such lesions?
are you diabetic or have any other medical condition?
Try to avoid wearing this ring till you see your doctor.
Lets us know what he says and also if you have any other queries.