Hydroxychloroquine sulfate tablets can be taken before meals or after meals, and the effect of diet on this drug is not obvious. This drug is mainly applicable to rheumatoid arthritis, juvenile chronic arthritis, discoid and systemic lupus erythematosus, as well as skin lesions caused or aggravated by sunlight. This drug can be used for adults and children, but different doses and administration times need to be selected according to the condition. Some patients may have adverse reactions after taking this drug, such as visual effects, skin effects, gastrointestinal effects, central nervous system effects, neuromuscular effects, cardiovascular system effects, hematological effects, liver effects, and possibly allergic reactions.