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 cyanide Hydroxychloroquine myositis K63 ub after chloroquine Plaquenil before surgery Hydroxychloroquine side effects may vary greatly from very mild side effects that go away with time to severe side effects like eye damage, ear damage, or heart problems. Some side effects may be experienced as the body adjusts to hydroxychloroquine but may diminish as the body becomes used to the drug. The more common side effects that can occur with hydroxychloroquine include headache. dizziness. diarrhea. stomach cramps. vomiting. 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. 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. Side effects of hydroxychloroquine medication Side Effects of Plaquenil Hydroxychloroquine, Warnings, Uses, Hydroxychloroquine Side Effects, Dosage, Uses, and More Plaquenil and plastic surgery These medications may interact and cause very harmful effects. Consult your healthcare professional e.g. doctor or pharmacist for more in formation. HYDROXYCHLOROQUINE/POSSIBLE QT PROLONGING AGENTS Hydroxychloroquine Oral Interactions with Other Medication. Plaquenil Hydroxychloroquine - Side Effects, Dosage.. Hydroxychloroquine Indications, Side Effects, Warnings -. Apr 10, 2019 Common Plaquenil side effects may include headache, dizziness, ringing in your ears; nausea, vomiting, stomach pain; loss of appetite, weight loss; mood changes, feeling nervous or irritable; skin rash or itching; or. hair loss. Check with your doctor immediately if any of the following side effects occur Incidence not known. Blistering, peeling, loosening of the skin blurred vision or other vision changes chest discomfort, pain, or tightness cough or hoarseness dark urine decreased urination defective color vision diarrhea difficulty breathing Tell your doctor right away if you have any serious side effects, including arm/leg/back pain, slow/fast/irregular heartbeat, symptoms of heart failure such as shortness of breath, swelling ankles/feet, unusual tiredness, unusual/sudden weight gain, hair loss/color change, mental/mood changes e.g. anxiety, depression, rare thoughts of suicide, hallucinations, ringing in the ears/hearing loss, worsening of skin conditions e.g. psoriasis, severe stomach/abdominal pain, severe nausea.