When hydroquinone turns brown, is it still safe to use?
Thank you for reading Tara! No, the hydroquinone won’t hurt you if it turns brown but it won’t be effective either because it has oxidized or degraded. I would recommend throwing it out after a year or sooner, if it turns brown throughout the tube. Sometimes, just the first 1/4 cm will turn brown right at the mouth of the tube but the rest will be fine.
I’m guessing that if you use a light scrub on the area a couple of times, that yellowish color will disappear.
Hope this helps, Dr. I
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