Too much of niacinamide can cause irritation and redness on the face.
Studies show that upto 5% niacinamide is enough to deliver the benefits that niacinamide can to the face. Anything higher, can cause irritation in some people.
Irritation and redness on the face can eventually lead to dark spots / pigmentation on the face.
A couple of scenarios…
Your skin is irritated, and if the product has more than 5% niacinamide
Then maybe that’s too much niacinamide for your skin. Stop using that product.
Your skin is irritated, and if the product has 5% or less niacinamide
Before you stop using it, check the following: