Hydroxychloroquine 400 mg Tablet

Antimalarial used mainly as a disease-modifying anti-rheumatic drug (DMARD) for:

• Rheumatoid arthritis (alone or with methotrexate/sulfasalazine)
• Systemic lupus erythematosus and discoid lupus
• Sjögren's syndrome, some photosensitive skin conditions
• Malaria (treatment/prevention where chloroquine-sensitive)

Rheumatoid arthritis / lupus (adults): 200–400 mg daily (as one dose or two divided doses); do not exceed 5 mg/kg/day of actual body weight (reduces eye toxicity).

• Benefit may take 2–6 months to appear.

Children (juvenile arthritis/lupus, specialist): up to 5 mg/kg/day (max 400 mg).

Malaria prevention: 400 mg once weekly, from 1–2 weeks before travel to 4 weeks after.

• Take with food or milk.

• Allergy to 4-aminoquinolines
• Pre-existing maculopathy (retinal damage)
• Children under 6 years (tablets not suitable)

Common: nausea, abdominal pain, diarrhoea, headache, rash, itching, loss of appetite, mood changes.

Less common: skin pigmentation, hair bleaching/loss, dizziness, tinnitus, blurred vision (temporary).

Rare but serious: retinal damage (retinopathy) with long-term use — can be permanent; QT prolongation/arrhythmias, cardiomyopathy; low blood sugar; severe skin reactions (DRESS, SJS); muscle weakness; blood disorders; haemolysis in G6PD deficiency; psychiatric effects including suicidal thoughts.

• Baseline eye examination within the first year, then yearly screening after 5 years (sooner if risk factors such as kidney disease or higher doses).
• Report any change in vision, palpitations, fainting, low-sugar symptoms or mood changes.
• Heart disease, kidney or liver impairment, epilepsy, psoriasis, porphyria, G6PD deficiency: caution.
• Keep away from children (dangerous in overdose).

Generally continued in pregnancy for lupus (stopping may cause flares — benefit outweighs risk). Compatible with breastfeeding.

• QT-prolonging drugs (azithromycin, macrolides, quinolones, antipsychotics, amiodarone) — arrhythmias
• Insulin and diabetes medicines (hypoglycaemia)
• Digoxin, ciclosporin (levels rise)
• Antacids, kaolin (take 4 hours apart)
• Antiepileptics (may lower seizure threshold); mefloquine

Dangerous: headache, visual disturbance, drowsiness, convulsions, low blood pressure, arrhythmias, cardiac arrest — emergency hospital care.

Store below 30°C, out of reach of children.