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Quick facts
- How it is given
- oral
- Type
- human prescription drug
- RxNorm ID
- 979092
We do not publish dosing. How much of this medicine to take, how often, and for how long depends on your age, weight, kidney and liver function, other conditions and other medicines. That is a decision for the person who prescribes or dispenses it. Follow the directions on your own pack and ask your pharmacist if anything is unclear.
What it is used to treat
Hydroxychloroquine sulfate tablets are an antimalarial and antirheumatic indicated for the: Treatment of uncomplicated malaria due to Plasmodium falciparum, Plasmodium malariae, Plasmodium ovale, and Plasmodium vivax in adult and pediatric patients. ( 1.1 ) Prophylaxis of malaria in geographic areas where chloroquine resistance is not reported in adult and pediatric patients. ( 1.1 ) Treatment of rheumatoid arthritis in adults. ( 1.2 ) Treatment of systemic lupus erythematosus in adults. ( 1.3 ) Treatment of chronic discoid lupus erythematosus in adults. ( 1.4 ) Limitations of Use ( 1.1 ): Hydroxychloroquine sulfate tablets are not recommended for the: Treatment of complicated malaria. Treatment of chloroquine or hydroxychloroquine-resistant strains of Plasmodium species. Treatment of malaria acquired in geographic areas where chloroquine resistance occurs or when the Plasmodium species has not been identified. Prophylaxis of malaria in geographic areas where chloroquine resistance occurs. Prevention of relapses of P. vivax or P. ovale because it is not active against the hypnozoite liver stage forms of these parasites. For radical cure of P. vivax and P. ovale infections, concomitant therapy with an 8-aminoquinoline drug is necessary. 1.1 Malaria Hydroxychloroquine sulfate tablets are indicated in adult and pediatric patient for the: Treatment of uncomplicated malaria due to Plasmodium falciparum, Plasmodium malariae, Plasmodium vivax, and Plasmodium ovale. Prophylaxis of malaria in geographic areas where chloroquine resistance is not reported. Limitations of Use : Hydroxychloroquine sulfate tablets are not recommended for: Treatment of complicated malaria. Treatment of malaria by chloroquine or hydroxychloroquine-resistant strains of Plasmodium species [see Microbiology (12.4) ]. Treatment of malaria acquired in geographic areas where chloroquine resistance occurs or when the Plasmodium species has not been identified. Prophylaxis of malaria in geographic areas where chloroquine resistance occurs. Prevention of relapses of P. vivax or P. ovale because it is not active against the hypnozoite liver stage forms of these parasites. For radical cure of P. […]
About this medicine
Hydroxychloroquine sulfate tablets, USP is an antimalarial and antirheumatic drug, chemically described as 2-[[4-[(7-Chloro-4-quinolyl)amino]pentyl]ethylamino] ethanol sulfate (1:1) with the molecular formula C 18 H 26 ClN 3 O•H 2 SO 4 . The molecular weight of hydroxychloroquine sulfate is 433.95. Its structural formula is: Hydroxychloroquine sulfate, USP is a white or practically white crystalline powder, freely soluble in water; practically insoluble in alcohol, chloroform and ether. Hydroxychloroquine sulfate tablets, USP 200 mg for oral administration contain 200 mg hydroxychloroquine sulfate (equivalent to 155 mg of hydroxychloroquine) and the following inactive ingredients: corn starch, pregelatinized starch, anhydrous dibasic calcium phosphate, magnesium stearate, hypromellose 2910(3 mPas), hydroxypropyl cellulose, titanium dioxide, polyethylene glycol 400, hypromellose 2910(50 mPas). Image
How it works
12.1 Mechanism of Action Malaria Hydroxychloroquine is a 4-aminoquinoline antimalarial [see Microbiology (12.4) ] and antirheumatic agent. Rheumatoid Arthritis, Systemic Lupus Erythematosus and Chronic Discoid Lupus Erythematosus The mechanisms underlying the anti-inflammatory and immunomodulatory effects of hydroxychloroquine sulfate tablets in the treatment of rheumatoid arthritis, chronic discoid lupus erythematosus and systemic lupus erythematosus are not fully known.
Who should not take it
Hydroxychloroquine sulfate tablets are contraindicated in patients with known hypersensitivity to 4-aminoquinoline compounds. Patients with hypersensitivity to 4-aminoquinoline compounds ( 4 )
Warnings and cautions
Cardiomyopathy and Ventricular Arrhythmias : Fatal or life-threatening cardiomyopathy and ventricular arrhythmias were reported. ( 5.1 ) Retinal Toxicity : Irreversible retinal damage is related to cumulative dosage and treatment duration. Baseline retinal exam and exams during treatment are recommended. ( 5.2 ) Serious Skin Reactions : Stevens Johnson syndrome, toxic epidermal necrolysis, drug reaction with eosinophilia and systemic symptoms, acute generalized exanthematous pustulosis have been reported. ( 5.3 ) Worsening of Psoriasis : Avoid in patients with psoriasis. ( 5.4 ) Risks Associated with Use in Porphyria : Avoid in patients with porphyria. Hepatotoxicity was reported in patients with porphyria cutanea tarda ( 5.5 ). Hematologic Toxicity : Discontinue if myelosuppression occurs. ( 5.6 ) Renal Toxicity : Consider phospholipidosis as a possible cause of renal injury in patients with underlying connective tissue disorders. Discontinue hydroxychloroquine sulfate tablets if renal toxicity is suspected or demonstrated by tissue biopsy in any organ system. ( 5.1 , 5.8 , 5.11 ) 5.1 Cardiomypathy and Ventricular Arrhythmias Fatal and life-threatening cases of cardiotoxicity, including cardiomyopathy, have been reported in patients treated with hydroxychloroquine sulfate tablets. Signs and symptoms of cardiac compromise have occurred during acute and chronic hydroxychloroquine sulfate tablets treatment. In multiple cases, endomyocardial biopsy showed association of the cardiomyopathy with phospholipidosis in the absence of inflammation, infiltration, or necrosis. Drug-induced phospholipidosis may occur in other organ systems [see Warnings and Precautions ( 5.8 , 5.11 )]. Patients may present with ventricular hypertrophy, pulmonary hypertension and conduction disorders including sick sinus syndrome. ECG findings include atrioventricular, right or left bundle branch block. Hydroxychloroquine sulfate tablets has a potential to prolong the QT interval. Ventricular arrhythmias (including torsades de pointes) have been reported in hydroxychloroquine sulfate tablets-treated patients. […]
Reported side effects
The following adverse reactions are described in greater detail in other sections: Cardiomyopathy and Ventricular Arrhythmias [see Warnings and Precautions (5.1) ] Retinal Toxicity [see Warnings and Precautions (5.2) ] Serious Skin Reactions [see Warnings and Precautions (5.3) ] Worsening of Psoriasis [see Warnings and Precautions (5.4) ] Risks Associated with Use in Porphyria [see Warnings and Precautions (5.5) ] Hematologic Toxicity [see Warnings and Precautions (5.6) ] Hemolytic Anemia Associated with G6PD [see Warnings and Precautions (5.7) ] Skeletal Muscle Myopathy or Neuropathy [see Warnings and Precautions (5.8) ] Neuropsychiatric Reactions Including Suicidality [see Warnings and Precautions (5.9) ] Hypoglycemia [see Warnings and Precautions (5.10) ] Renal Toxicity [see Warnings and Precautions (5.11) ] The following adverse reactions have been identified during post-approval use of 4-aminoquinoline drugs, including hydroxychloroquine sulfate tablets. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure: Blood and lymphatic system disorders : Bone marrow depression, anemia, aplastic anemia, agranulocytosis, leukopenia, thrombocytopenia Cardiac disorders : Cardiomyopathy, cardiac failure, QT-interval prolongation, ventricular tachycardia, torsades de pointes, atrioventricular block, bundle branch block, sick sinus syndrome, pulmonary hypertension Ear and labyrinth disorders : Vertigo, tinnitus, nystagmus, sensorineural hearing loss Eye disorders : Retinopathy, retinal pigmentation changes (typically bull's eye appearance), visual field defects (paracentral scotomas), macular degeneration, corneal edema, corneal opacities, decreased dark adaptation Gastrointestinal disorders : Nausea, vomiting, diarrhea, abdominal pain General disorders : Fatigue Hepatobiliary disorders : Abnormal liver function tests, fulminant hepatic failure Immune system disorders : Urticaria, angioedema, bronchospasm Metabolism and nutrition disorders : Anorexia, hypoglycemia, weight loss Musculoskeletal and connective tissue disorders : P […]
Interactions with other medicines
Drugs Prolonging QT Interval and Other Arrhythmogenic Drugs. ( 7.1 ) See FPI for more important drug interactions. ( 7 ) 7.1 Drugs Prolonging QT Interval and Other Arrhythmogenic Drugs Hydroxychloroquine sulfate tablets prolongs the QT interval. There may be an increased risk of inducing ventricular arrhythmias if hydroxychloroquine sulfate tablets are used concomitantly with other arrhythmogenic drugs. Therefore, hydroxychloroquine sulfate tablets are not recommended in patients taking other drugs that have the potential to prolong the QT interval or are arrhythmogenic [see Warnings and Precautions (5.1) ]. 7.2 Insulin or Other Antidiabetic Drugs Hydroxychloroquine sulfate tablets may enhance the effects of insulin and antidiabetic drugs, and consequently increase the hypoglycemic risk. Therefore, a decrease in dosage of insulin and other antidiabetic drugs may be necessary [see Warnings and Precautions (5.10) ]. 7.3 Drugs that Lower the Seizure Threshold Hydroxychloroquine sulfate tablets can lower the seizure threshold. Co-administration of hydroxychloroquine sulfate tablets with other antimalarials known to lower the seizure threshold (e.g., mefloquine) may increase the risk of seizures. 7.4 Antiepileptics The activity of antiepileptic drugs might be impaired if co-administered with hydroxychloroquine sulfate tablets. 7.5 Methotrexate Concomitant use of hydroxychloroquine sulfate tablets and methotrexate may increase the incidence of adverse reactions. 7.6 Cyclosporine An increased plasma cyclosporine level was reported when cyclosporine and hydroxychloroquine sulfate tablets were co-administered. Monitor serum cyclosporine levels closely in patients receiving combined therapy. 7.7 Digoxin Concomitant hydroxychloroquine sulfate tablets and digoxin therapy may result in increased serum digoxin levels. Monitor serum digoxin levels closely in patients receiving combined therapy. 7.8 Cimetidine Concomitant use of cimetidine resulted in a 2-fold increase of exposure of chloroquine, which is structurally related to hydroxychloroquine. Interaction of cimetidine with hydroxychloroquine cannot be ruled out. Avoid concomitant use of cimetidine. […]
Use in specific groups
8.1 Pregnancy Pregnancy Exposure Registry There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to hydroxychloroquine sulfate tablets during pregnancy. Encourage patients to register by contacting 1-877-311-8972. Risk Summary Prolonged clinical experience over decades of use and available data from published epidemiologic and clinical studies with hydroxychloroquine sulfate tablets use in pregnant women have not identified a drug-associated risk of major birth defects, miscarriage, or adverse maternal, or fetal outcomes (see Data) . There are risks to the mother and fetus associated with untreated or increased disease activity from malaria, rheumatoid arthritis, and systemic lupus erythematosus in pregnancy (see Clinical Considerations) . Animal reproduction studies were not conducted with hydroxychloroquine. The estimated background risk of major birth defects and miscarriage for the indicated populations is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the US general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15-20%, respectively. Clinical Considerations Disease-Associated Maternal and/or Embryo-Fetal Risk Malaria : Malaria during pregnancy increases the risk for adverse pregnancy outcomes, including maternal anemia, prematurity, spontaneous abortion, and stillbirth. Rheumatoid Arthritis : Published data suggest that increased disease activity is associated with the risk of developing adverse pregnancy outcomes in women with rheumatoid arthritis Adverse pregnancy outcomes include preterm delivery (before 37 weeks of gestation), low birth weight (less than 2500 g) infants, and small for gestational age at birth. Systemic Lupus Erythematosus : Pregnant women with systemic lupus erythematosus, especially those with increased disease activity, are at increased risk of adverse pregnancy outcomes, including spontaneous abortion, fetal death, preeclampsia, preterm birth, and intrauterine growth restriction. […]
If too much is taken
Hydroxychloroquine sulfate tablets overdosage symptoms have an onset within 1–3 hours of ingestion. The following have been reported with hydroxychloroquine sulfate tablets overdosage: Cardiovascular toxicity, including QRS or QTc prolongation, ventricular tachycardia, ventricular fibrillation, torsade de pointes, atrioventricular block, cardiac arrest and death. Life-threatening hypotension is common. Severe hypokalemia secondary to an intracellular shift is common in severe toxicity. Central nervous system (CNS) depression, seizures, visual disturbances, transient blindness, and coma may occur. Gastrointestinal decontamination procedures warrant consideration in patients that present within the first hour post-ingestion. If the level of consciousness rapidly deteriorates in severe poisoning, consider intubation before gastrointestinal decontamination procedures. Monitor plasma potassium levels and manage accordingly. Hemofiltration, hemodialysis, and hemoperfusion are not of benefit. Consider contacting a poison center (1-800-221-2222) or a medical toxicologist for overdosage management recommendations.
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This page is built from the openFDA record of the U.S. Food and Drug Administration's approved labelling for this product, effective 9 October 2025. Label text has been shortened and reformatted for readability; safety wording has not been altered in meaning. FDA labelling describes products approved in the United States — brand names, strengths, formulations and approved uses may differ in your country. Always read the leaflet that comes with your own pack. PocketsInfo is not affiliated with, and is not endorsed by, the FDA. Retrieved 2026-07-30.