Isotretinoin, in a isotretinoin 20 mg dosage, is a medication prescribed to treat severe and persistent forms of acne, particularly those that are unresponsive to other treatments. This oral retinoid, a derivative of vitamin A, is known for its effectiveness in managing stubborn acne. Isotretinoin exerts control over the sebaceous (oil) glands in the skin, resulting in a reduction in sebum production. High sebum levels can contribute to clogged pores and acne formation.