HCQS 200mg tablet is also used for the treatment of rheumatoid arthritis and systemic lupus erythematosus. Hydroxychloroquine at a dose of 400 mg is also used as an adjunctive treatment for type 2 diabetes. The tablet has side effects such as headache, nausea, vomiting, loss of appetite, diarrhea, stomach upset, and more. These side effects may go away on their own. However, consult your doctor if they persist or worsen. The 200 mg HCQS tablet is a prescription medicine. Take with food to avoid stomach upset. Your doctor will determine the dosage and duration of treatment based on your clinical condition. Do not exceed the recommended dose. Avoid stopping this medication without consulting your doctor, as this may worsen your condition. The tablet contains hydroxychloroquine, an anti-inflammatory drug. In diabetes, it works by improving insulin sensitivity and increasing insulin secretion. In rheumatoid arthritis, hydroxychloroquine acts as a mild immunosuppressant and disease-modifying antirheumatic drug and inhibits the production of rheumatoid factor.