Korean doctors used these anti-malaria drugs to treat COVID-19 with some success, according to a paper filed with Elsevier in March 2020, but effectiveness is unproven.
What are the side effects of hydroxychloroquine (Plaquenil)?
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).
Rare but potentially serious eye toxicity can occur. This toxicity affects a part of the eye called the retina and can lead to color blindness and even loss of vision. An ophthalmologist (eye specialist) often can detect changes in the retina that suggest toxicity before serious damage occurs. Therefore, regular eye examinations, even when there are no symptoms, are mandatory.
Patients who are genetically deficient in a certain enzyme, called G6PD, can develop a severe anemia resulting from the rupture of red blood cells. This enzyme deficiency is more common in persons of African descent and can be evaluated by blood testing. Hydroxychloroquine may worsen psoriasis.