How is ATRALIN different compared to other retinoids? I am actually applying it every three nighs because my skin gets irritated and peels. I have been applying it every three days for the last 4 months and still my skin hasn't got used to it. I wonder if I shouldn't bother at all at this point because I might be using this ATRALIN not as often as I should. Lastly, light inactivates retinoids. Does artificial light do that too? Should I apply retinoids in a dark room?