Although not all of these side effects may occur, if they do occur they may need medical attention. Check with your doctor immediately if any of the following side effects occur while taking hydroxychloroquine: Incidence not known Some side effects of hydroxychloroquine may occur that usually do not need medical attention. Plaquenil and infection risk Lyme and plaquenil Reddit askreddit plaquenil Does plaquenil cause low white blood cell count Side Effects. Drug information provided by IBM Micromedex Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention. Plaquenil is the brand name for the prescription drug hydroxychloroquine. It's used to treat and prevent malaria infection, and to reduce symptoms and progression of autoimmune diseases such as lupus, rheumatoid arthritis, and others. Malaria is spread by mosquitoes. In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345. List Hydroxychloroquine Powder side effects by likelihood and severity. Save up to 80% on your prescription with WebMDRx. Consult your pharmacist or physician. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. These side effects may go away during treatment as your body adjusts to the medicine. What are the side effects of the drug hydroxychloroquine What are the side effects of hydroxychloroquine and., Plaquenil Hydroxychloroquine - Side Effects, Dosage. Ra treatment plaquenil methotrexateHuman anti-chimeric antibody rituximab hydroxychloroquineUsual dose of plaquenilTaking hydroxychloroquineChloroquine phosphate for marine velvet Get medical help right away if you have any very serious side effects, including sensitivity to light, vision changes e.g. blurred vision, seeing light flashes/streaks/halos, missing/blacked-out areas of vision, muscle weakness, numbness/tingling/pain of the arms/legs. Hydroxychloroquine Oral Uses, Side Effects, Interactions.. Hydroxychloroquine Sulfate Bulk Uses, Side Effects.. Long-Term Side Effects of Plaquenil for Rheumatoid Arthritis.. Severe side effects may include allergic reactions. It appears to be safe in pregnancy but this use has not been well studied. Hydroxychloroquine is in the antimalarial and 4-aminoquinoline families of medication. Hydroxychloroquine was approved for medical use in the United States in 1955. Chloroquine has been replaced with hydroxychloroquine as it has less side effects. Eye Exam Before Starting Treatment. If a person is going to be treated long-term with Plaquenil, they need to have a thorough dilated eye exam with best corrected visual acuity, central visual field, color vision, and dilated examination of the retina. What Are The Side Effects Though hydroxychloroquine may be effective, it does have the potential of causing numerous side effects, including but not limited to headache, loss of appetite, nausea.