It does not work against certain types of malaria (chloroquine-resistant). The United States Center for Disease Control provides updated guidelines and travel recommendations for the prevention and treatment of malaria in different parts of the world. How does plaquenil work for sjogren& 39 How long does it take for hydroxychloroquine to work Plaquenil. Uses. Hydroxychloroquine is used to prevent or treat malaria infections caused by mosquito bites. It does not work against certain types of. Side Effects. Precautions. Interactions. Hydroxychloroquine brand name Plaquenil, Plaquenil Sulfate is a medicine used to treat rheumatoid arthritis and other inflammatory conditions such as systemic lupus erythematosus SLE/Lupus. Hydroxychloroquine is also an antimalarial medicine used to prevent and treat malaria and other parasitic infections. PLAQUENIL hydroxychloroquine sulfate tablets is indicated for the treatment of rheumatoid arthritis, and discoid and systemic lupus erythematosus, in patients who have not responded satisfactorily to drugs with less potential for serious side effects. This medication is also used, usually with other medications, to treat certain auto-immune diseases (lupus, rheumatoid arthritis) when other medications have not worked or cannot be used. Discuss the most recent information with your doctor before traveling to areas where malaria occurs. Hydroxychloroquine precautions Hydroxychloroquine - Side Effects, Dosage, Interactions., ATIENT NFORMATION ON HYDROXYCHLOROQUINE Hydroxychloroquine sulfate tablets usp 200 mg uses PRECAUTIONS Before taking hydroxychloroquine, tell your doctor or pharmacist if you are allergic to it; or to other aminoquinolines e.g. chloroquine; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. HYDROXYCHLOROQUINE - ORAL Plaquenil side effects.. Plaquenil Hydroxychloroquine Sulfate. Hydroxychloroquine Indications, Side Effects, Warnings.. Over the long term hydroxychloroquine can reduce pain, swelling and joint stiffness. If you have lupus, it may also improve the rash. It may be as long as 12 weeks before you notice the benefits. Hydroxychloroquine is often taken in combination with other drugs such as methotrexate. Some warnings and precautions to be aware of with hydroxychloroquine include the following Hydroxychloroquine can damage the retina of the eye. This can lead to blindness. This problem is most common when high doses are taken for a long time. Final Thoughts on Plaquenil Warnings and Precautions. There are a number of situations in which Plaquenil should not be taken, along with several precautions and warnings people should be aware of before starting the medication. However, it is possible that not all of the warnings or precautions with Plaquenil were discussed in this article.