Hydroxychloroquine is available as the brand-name drug Plaquenil. Generic drugs usually cost less than the brand-name version. Hydroxychloroquine may be used as part of a combination therapy. Vision test for plaquenil What does hydroxychloroquine sulphate do Plaquenil pill doses Visual field testing for plaquenil toxicity The usual starting dose of Plaquenil is 200 mg twice a day or 400 mg once a day, administered orally, in people weighing 80 kg or more. The usual dosage works for most people who take Plaquenil, but it is possible to increase or decrease the dose based on individual needs. It's important to watch for possible side effects and toxicity. There is a small risk that hydroxychloroquine can damage your retina part of the eye, and this increases with long-term use and higher dosage. Your doctor will advise you on a safe dose to take according to your weight, and you will need to have regular monitoring of your eyes. What does Plaquenil do? Plaquenil relieves pain and swelling and prevents damage to joints. How long does Plaquenil take to work? Plaquenil works very slowly. In 1 to 3 months you should start to feel better. You may continue to get better for up to 1 year. Most people who take Plaquenil also take other medicines for pain and stiffness. Hydroxychloroquine is used to treat lupus erythematosus and rheumatoid arthritis. It isn’t fully understood how this drug works to treat lupus erythematosus or rheumatoid arthritis. That means you may need to take it with other drugs. It treats malaria by killing the parasites that cause the disease. How long to take plaquenil Hydroxychloroquine Side Effects, Dosage, Uses, and More, Hydroxychloroquine Side-effects, uses, time to work Molecular formula chloroquine If you are taking hydroxychloroquine over a long duration, it is important to take eye exams every 6 to 12 months. 6 Do not take hydroxychloroquine if you experience vision symptoms, including problems seeing or reading, light sensitivity, blurred distance vision, or light flashes or streaks. 5 Hydroxychloroquine Plaquenil -. Lupus Medicines Hydroxychloroquine - Brigham and Women's Hospital. Plaquenil Hydroxychloroquine - Side Effects, Dosage.. Hydroxychloroquine Plaquenil is considered a disease-modifying anti-rheumatic drug DMARD. It can decrease the pain and swelling of arthritis. It may prevent joint damage and reduce the risk of long-term disability. Hydroxychloroquine is in a class of medications that was first used to prevent and treat malaria. How long does it take for plaquenil to work? I just started about 6 weeks ago, the rheum said it can take up to a year. Let me know how you are doing on it. If you are also taking kaolin or antacids, take them at least 4 hours before or after using hydroxychloroquine. Dosing. The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine.