Plaquenil sometimes affects our eyes. What it does is constrict the field of view. That is, takes away some of our peripheral vision.
The test is usually a big round box-like thing, you look into one eye at a time. You click a button every time you see a light flash. It flashes all over at different places randomly. They can tell from your clicks if your field of view is being negatively affected by plaquenil.
You need to have this test every year. If they detect an issue, you will be instructed to stop taking it and your eyes will return to normal.
Lynnwood, Lupus & Sjogren's Moderator, Dx: 2002DIAGNOSING LUPUS & LUPUS RESOURCES
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