Hi @Gingergrrl - that's too bad you can't take or use magnesium. You may have told me this before, I can't remember. Because I've had such good results with the topically applied magnesium oil, I would try the peppermint oil and thyme oil which have also been suggested. And I'm sure it would be good to get testing done (MRI I guess, as someone suggested) to try to find out what is going on.
Re your retina - I don't think flashing lights are a part of "normal" aging, plus you're not very old at all anyways!
I worked with a woman once who suddenly developed flashing light in one eye. This was many years ago but as I recall, she was told to get into the doctor right away. Her retina was detaching or detached but they were able to fix it. But I think if she had waited, it would have been much more problematic. All I can tell you is, get it checked out. It's fixable if your retina is having problems, but do get it checked sooner rather than later - okay, end of lecture!
You (and others) have now convinced me now that I should make an appt w/either my optometrist (who I've seen for regular eye exams, glasses & contacts since I was 18 yrs old) or the opthamologist who I've seen a few times (but I like her and she is very smart and thorough). I have to try to prioritize all of this stuff b/c my next IVIG is next Th & Fri (and then I will feel sick for 3-4 days recovering from IVIG plus have my dog back home at the same time and be taking care of her again).