Malaria is common in areas such as Africa, South America, and Southern Asia. This medicine is not effective against all strains of malaria. Chloroquine diphophate salt Sulfasalazine and hydroxychloroquine Hydroxychloroquine oral tablet doesn’t cause drowsiness, but it can cause other side effects. More common side effects. The more common side effects that can occur with hydroxychloroquine include If your child is taking any drugs that can cause a certain type of heartbeat that is not normal prolonged QT interval. There are many drugs that can do this. Ask the doctor or pharmacist if you are not sure. This is not a list of all drugs or health problems that interact with this drug. Hydroxychloroquine Plaquenil is a drug that is classified as an anti-malarial drug. Plaquenil is prescribed for the treatment or prevention of malaria. It is also prescribed for the treatment of rheumatoid arthritis, lupus, and the side effects of lupus such as hair loss, joint pain, and more. Hydroxychloroquine may also be used for purposes not listed in this medication guide. Hydroxychloroquine is also used to treat symptoms of rheumatoid arthritis and discoid or systemic lupus erythematosus. Does hydroxychloroquine cause cancer Hydroxychloroquine Memorial Sloan Kettering Cancer Center, Hydroxychloroquine - Memorial Sloan Kettering Cancer Center Chloroquine alcoholHow long to take plaquenil for ra60 increase in malaria deaths after chloroquine failureNegative ana with plaquenil Some antacids can make it harder for your body to absorb hydroxychloroquine. Hydroxychloroquine can cause serious liver or heart problems, especially if you use certain medicines at the same time. Hydroxychloroquine - Side Effects, Dosage, Interactions - Drugs.. Hydroxychloroquine Plaquenil Side Effects & Dosage for Malaria. Long-Term Side Effects of Plaquenil for Rheumatoid Arthritis. Estrogen can cause the growth of breast cancer cells. Drugs, such as letrozole, may lessen the amount of estrogen made by the body. Giving hydroxychloroquine, palbociclib, and letrozole before surgery may work better than palbociclib and letrozole in treating participants with breast cancer. Lynwood, I can't answer your question about weight gain or loss on plaquenil but I did go off plaquenil a few months ago and haven't been the same since. I regret the decision which had I made because I'd felt pretty well for quite some time and was doing my best to slowly get off as many meds as possible. Apr 10, 2019 Plaquenil is also an antirheumatic medicine and is used to treat symptoms of rheumatoid arthritis and discoid or systemic lupus erythematosus. Important information. Taking Plaquenil long-term or at high doses may cause irreversible damage to the retina of your eye.