The best moisturizer I used is CeraVe moisturizing cream in the tub. It's not greasy or oily. It is thick and light at the same time and it settles into the skin quickly without leaving you shiny. I had no flaking on accutane when I used the moisturizer morning and night. Some days I used it in the afternoon as well. Seems like when you are on accutane your side effects of dryness goes up and down for no rhyme or reason.
Im using cerave in the pump one but its wayyyy to thin for me sadly. i honestly believed i would never get dry on this medicine...im on such a high dose that my whole body doesnt even produce oil anymore- i also had to switch my hair care routine- now i just use the head and shoulders for very dry hair- with like almond oil or whatever. good luck!