?Vitamin C Oxidation
This product contains hydroquinone and Vitamin C. Vitamin C is an unstable compound and oxidizes readily. This most likely accounts for the brown discoloration. While I doubt whether it is harmful, it probably has lost some potency. This is a prescription product due to its containing 4% Hydroquinone. It would be a good idea to ask the physician who prescribed it for another bottle if it was received in that condition.
(By the way, we once carried Skinceuticals, many of whose...