HCQS (Hydroxychloroquine 400 mg) is typically prescribed for short-term use in conditions like malaria and autoimmune diseases such as lupus and rheumatoid arthritis. The duration of HCQS treatment depends on the specific condition being treated and the individual's response to the medication. In some cases, it may be used for several months to years under medical supervision. Prolonged use requires regular monitoring for potential side effects on the eyes, heart, and blood glucose levels. Always follow your healthcare provider's guidance regarding the duration and usage of HCQS to ensure safe and effective treatment.