The most common cause is the tetracycline family.
Minocycline used long term for acne may cause this, and is the most common, I think.
Also excess intake of Vit A, the retinol form. (often a treatment by dermatologists for acne--but not as common now compared to a few years ago).
Here is an article about it:
http://www.nlm.nih.gov/medlineplus/e...cle/000351.htm
I have seen people use the Diamox (acetazolamide) or Lasix
(furosemide) for mild to moderate cases.
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All truths are easy to understand once they are discovered; the point is to discover them.-- Galileo Galilei
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Weezie looking at petunias 8.25.2017
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