HCQS 300 Tablet contains Hydroxychloroquine 300mg, an antimalarial and immunomodulatory agent primarily used in the treatment and prevention of malaria, as well as autoimmune diseases such as rheumatoid arthritis and systemic lupus erythematosus. Hydroxychloroquine acts by interfering with lysosomal activity and autophagy, modulating immune responses and reducing inflammation. It is indicated for the management of acute and chronic malaria caused by Plasmodium species, and for controlling symptoms and disease progression in autoimmune disorders. The tablet should be taken orally with or without food, as prescribed by a healthcare professional. Dosage and duration depend on the condition being treated, patient response, and tolerance. Common adverse effects include gastrointestinal disturbances such as nausea, vomiting, and abdominal discomfort, as well as headache and dizziness. Rare but serious side effects may involve retinopathy, cardiomyopathy, and myopathy; therefore, regular monitoring including ophthalmologic examinations is recommended during prolonged therapy. HCQS 300 Tablet is contraindicated in patients with known hypersensitivity to hydroxychloroquine or related compounds, pre-existing retinopathy, and certain cardiac conditions. Caution is advised in patients with hepatic or renal impairment. This medication should be used under strict medical supervision to ensure efficacy and minimize risks.