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Yes, niacinamide can be a good addition if you want to treat a darker skin tone in the underarm area, especially if the discoloration is caused by friction and irritation rather than shaving. Niacinamide is known to help even out skin tone and strengthen the skinâs protective barrier over time.
Please note that results often come gradually, and it can take several weeks or even months to notice a clear difference. If you are already using glycolic acid, itâs best to introduce niacinamide slowly to avoid irritation.
You could try The Ordinary Niacinamide 10% + Zinc 1%, for example.
Apply a few drops to clean, dry skin once a day at first. If your skin feels good, you can then increase usage to morning and evening.
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