Plaquenil is used to treat or prevent malaria, a disease caused by parasites that enter the body through the bite of a mosquito. Malaria is common in areas such as Africa, South America, and Southern Asia. Chloroquine malaria chemical formula Mechanism of action of hydroxychloroquine in rheumatoid arthritis Taking hydroxychloroquine long-term or at high doses may cause irreversible damage to the retina of your eye. Stop taking this medicine and call your doctor at once if you have trouble focusing, if you see light streaks or flashes in your vision, or if you notice any swelling or color changes in your eyes. If you take too much hydroxychloroquine, you may experience headaches, drowsiness, visual disturbances or fits. These symptoms may occur within 30 minutes of overdose. If you don't have to, don't stop your plaquenil. I stopped taking the plaquenil the beginning of December. It doesn't agree with my stomach I take it with meals too. And since I hadn't had a miraculous recovery the 6 months I'd been on it, I didn't think there was any harm in stopping it. Plaquenil is also an antirheumatic medicine and is used to treat symptoms of rheumatoid arthritis and discoid or systemic lupus erythematosus. This medicine is not effective against all strains of malaria. What happens if you take too much hydroxychloroquine Lupus Medicines Hydroxychloroquine - Brigham and Women's., APO-Hydroxychloroquine hydroxychloroquine sulfate Drug. Hydroxychloroquine discount cardHow much plaquenil medication costBisoprolol and hydroxychloroquineMetronidazole and levofloxacin and hydroxychloroquine Hydroxychloroquine can cause weakening of the heart muscle, resulting in heart your healthcare provider right away if you have some or all of the following symptoms of heart failure. breathlessness Hydroxychloroquine - Side Effects, Uses, Dosage, Overdose.. Stopping plaquenil. DailyStrength. Side Effects of Plaquenil Hydroxychloroquine, Warnings, Uses. Take Plaquenil with a meal or a glass of milk. To prevent malaria Start taking Plaquenil 2 weeks before entering an area where malaria is common. Continue taking the medicine regularly during your stay and for at least 8 weeks after you leave the area. To treat malaria Plaquenil is usually given for 3 days, starting with one high dose followed by a smaller dose during the next 2 days in a row. Take Plaquenil for the full prescribed length of time for malaria. The risk may also be higher with some doses of hydroxychloroquine, if you use hydroxychloroquine for longer than 5 years, or if you take certain other drugs like tamoxifen. Call your doctor right away if you have any eyesight changes like blurred or foggy eyesight, trouble focusing or reading, or trouble seeing in dim light. Here are side effect From taking too many antacids. The least important side effects are constipation or diarrhea. Large amounts of calcium carbonate -containing antacids can affect the balances of calcium and acid in the body and damage the kidneys.