Nu-Derm Exfoderm Forte is an exfoliating lotion for normal to oily skin types. Refresh your skin by using Obagi Nu-Derm Exfoderm Forte #4 to brighten your complexion. The top layer of skin typically contains dead skin cells and other irritants that can leave your face feeling dry and rough, but removing the outer layer exposes to soft skin underneath to make you look younger and healthier.