PLAQUENIL

What it is

Plaquenil contains hydroxychloroquine sulfate 200 mg (equivalent to 155 mg base) in film coated tablets.

Approved indications

— Rheumatoid arthritis — Mild systemic and discoid lupus erythematosus — Suppression and treatment of malaria

Dosing overview

For rheumatoid arthritis in adults, a suitable initial dosage is from 400 to 600 mg daily, preferably taken at meal times. When a good response is obtained (usually in four to twelve weeks) the dose can be reduced to 200 to 400 mg daily (but should not exceed 6 mg/kg per day) and can be continued as maintenance treatment. For mild systemic and discoid lupus erythematosus, an initial dose of 400–800 mg daily is recommended for adults. This level can be maintained for several weeks and then reduced to a maintenance dose of 200–400 mg daily. For malaria suppression, adults require 400 mg (310 mg base) on exactly the same day of each week. Children require a weekly suppressive dose of 5 mg (base) per kg bodyweight but this should not exceed the adult dose regardless of weight. For treatment of acute malaria attack in adults, an initial dose of 800 mg is followed by 400 mg in six to eight hours and 400 mg on each of two consecutive days (total dose of 2 g or 1.55 g base).

Key safety warnings

Cases of cardiomyopathy resulting in cardiac failure, in some cases with fatal outcome, have been reported in patients treated with Plaquenil. In multiple cases, endomyocardial biopsy showed association of the cardiomyopathy with phospholipidosis in the absence of inflammation, infiltration, or necrosis. Clinical monitoring for signs and symptoms of cardiomyopathy is advised and Plaquenil should be discontinued if cardiomyopathy develops. Serious cases of drug-induced liver injury (DILI) including hepatocellular injury, acute hepatitis and fulminant hepatic failure (including fatal cases) have been reported during use of Plaquenil. Prompt clinical evaluation and measurement of liver function tests should be performed in patients who report symptoms that may indicate liver injury. Irreversible retinal damage has been observed in some patients who had received long-term or high-dosage 4-aminoquinolone therapy for discoid and systemic lupus erythematosus, or rheumatoid arthritis. Retinopathy has been reported to be dose related. Exceeding the recommended daily dose sharply increases the risk of retinal toxicity. Before starting treatment with hydroxychloroquine, all patients should have a careful complete examination of both eyes which includes slit lamp microscopy for corneal changes, fundoscopy, visual acuity, central visual field and colour vision. A complete eye examination before treatment will determine the presence of any visual abnormalities, either coincidental or due to the disease and establish a baseline for further assessment of the patient's vision. Hydroxychloroquine has been shown to cause severe hypoglycaemia including loss of consciousness that could be life threatening in patients treated with and without anti-diabetic medications. Patients treated with hydroxychloroquine should be warned about the risk of hypoglycaemia and the associated clinical signs and symptoms. Hydroxychloroquine prolongs the QTc interval and should not be used in patients receiving drugs known to prolong the QT interval, such as class IA and III antiarrhythmics, tricyclic antidepressants, antipsychotics, some anti-infectives due to increased risk of ventricular arrhythmia.

Contraindications

Plaquenil is contraindicated in patients with pre-existing maculopathy of the eye, patients with known hypersensitivity to 4-aminoquinoline compounds, long-term therapy in children, and children under 6 years of age.

PBS listing

Information regarding PBS listing is not available in the provided source documents.

Regulatory history

Plaquenil hydroxychloroquine sulfate 200 mg tablets were first listed on the ARTG on 19 August 1994. In December 2025, the PBAC recommended an unrestricted increase in the maximum number of repeats per prescription from one to three repeats to support patient access and continuity of treatment.