Lactic Acid Resurfacing Night Serum hasn't been tested for use with retinol. If you have sensitive skin, it is always a good idea to do a patch test first. If you were to use a conventional retinol with this product a good practice would be to alternate days between this and your retinol product. A great alternative is Phyto-Retinol Serum, which can be used with this and doesn't have the same photosensitivity as traditional retinol. We suggest Phyto-Retinol Serum in the morning and Lactic Acid Resurfacing Night Serum at night. If you want to use them together, apply Phyto-Retinol Serum first, then layer Lactic Acid Resurfacing Night Serum over.