I have oily skin and this product did absolutely nothing to control the oil on my face even after consistent use of more than 1 month. I have used niacinamide serum of other brand with lower concentration of niacinamide and have worked to control oiliness of my skin to an extent. But I am very disappointed to say that this product did nothing. It is a sticky solution. Just 3 drops is necessary for entire face. Spreads nicely. The dropper cap is not very secure as it leaked a bit when the bottle was not kept upright. There was no bad reactions. Bottom line...... It seemed to be a good product with good reviews but.... It did nothing for me.