Is there a way to treat dry skin due to Accutane?

The way Accutane (isotretinoin) works to fight acne is by shrinking oil-producing glands—but those oils that cause acne are also what self-moisturize the skin.¹ So a common side effect of Accutane is dry skin, especially around the lips/mouth.² That dry skin is treatable in the same ways mentioned earlier, by using moisturizing creams containing hydrating ingredients, like petroleum jelly (especially for the lip/mouth area), aloe vera, Vitamins C and E, ceramides, etc.

References:
¹Oral isotretinoin for acne by Caroline S Costa, Ediléia Bagatin, Ana Luiza C Martimbianco, Edina MK da Silva, Marília M Lúcio, Parker Magin, Rachel Riera, and Cochrane Skin Group. Cochrane Library.
²Treatment of acne with intermittent and conventional isotretinoin: a randomized, controlled multicenter study by Ayse Akman, Cicek Durusoy, Meltem Senturk, Cilem Kaya Koc, Durali Soyturk, and Erkan Alpsoy. Archives of Dermatological Research.