Malaria is common in areas such as Africa, South America, and Southern Asia. This medicine is not effective against all strains of malaria. Hydroxychloroquine chemotherapy Chloroquine phosphate cryptocaryon 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. Check with your doctor immediately if any of the following side effects occur while taking hydroxychloroquine Incidence not known Blistering, peeling, loosening of the skin Hydroxychloroquine typically is very well tolerated. Serious side effects are rare. The most common side effects are nausea and diarrhea, which often improve with time. Less common side effects include rash, changes in skin pigment such as darkening or dark spots, hair changes, and muscle weakness. Taking hydroxychloroquine long-term or at high doses may cause irreversible damage to the retina of your eye. Hydroxychloroquine is also an antirheumatic medicine and is used to treat symptoms of rheumatoid arthritis and discoid or systemic lupus erythematosus. Hydroxychloroquine bad side effects Common and Rare Side Effects for Plaquenil Oral, Plaquenil Side Effects Common, Severe, Long Term - Chloroquine plus proguanilPlaquenil dose for discoid lupusCan you take phenylephrine with plaquenilAnti malaria pills chloroquine Side effects include irritability, headache, weakness, hair lightening or loss, stomach upset, nausea, dizziness, muscle pain, rash and itching. Rarely, hydroxychloroquine can affect the bone marrow leading to reduced white blood cells leukopenia or platelets thrombocytopenia and abnormal red blood cells anemia. Hydroxychloroquine Plaquenil Side Effects & Dosage for Malaria. Hydroxychloroquine Plaquenil. Hydroxychloroquine Reviews Everyday Health. Side effects are uncommon; however, a few people may develop a rash, indigestion, diarrhoea, headache, blurred vision, darkening of the skin, or bleaching of the hair. Hydroxychloroquine can aggravate pre-existing psoriasis. Common 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. Nov 18, 2013 Bad Side Effects of Plaquenil. I have been recently diagnosed with Lupus about 4 months ago and have started plaquenil with the hope it would relieve my symptoms no energy, achy body and severe hair loss. It seems as though it has helped the first two symptoms, but I have horrible constipation.