Isotane 20 Capsule contains isotretinoin 20 mg, a retinoid derivative primarily indicated for the treatment of severe recalcitrant nodular acne that is unresponsive to conventional therapies such as antibiotics and topical agents. Isotretinoin acts by reducing sebaceous gland size and sebum production, inhibiting the growth of acne-causing bacteria, and exerting anti-inflammatory effects, thereby addressing multiple pathogenic factors of acne. The capsule formulation ensures precise dosing and systemic absorption. Due to its potent teratogenicity, Isotane 20 must be prescribed with strict adherence to pregnancy prevention programs, including effective contraception for women of childbearing potential before, during, and after treatment. Common adverse effects include dryness of skin and mucous membranes, cheilitis, and photosensitivity; more serious but less frequent effects involve hepatic enzyme elevation, hyperlipidemia, and mood changes, necessitating regular monitoring of liver function tests, lipid profiles, and mental health status. Isotane 20 is contraindicated in pregnancy, hypersensitivity to isotretinoin, and patients with hepatic impairment or hyperlipidemia. The treatment duration typically ranges from 15 to 20 weeks, with dosage adjustments based on clinical response and tolerability. Patient education on adherence, side effect management, and follow-up is essential to optimize therapeutic outcomes and minimize risks.