The most powerful acne treatment is isotretinoin, also known as Accutane. This oral medication is a retinoid that effectively treats severe, recalcitrant acne. It works by reducing oil production, preventing the formation of comedones (blackheads and whiteheads), and reducing inflammation. Isotretinoin is highly effective, but it can have serious side effects, including birth defects, liver damage, and mood changes. Therefore, it's only prescribed for severe acne that doesn't respond to other treatments and must be taken under strict medical supervision.