Chloroquine

1 medicine

Chloroquine is an antimalarial and antirheumatic drug that can cause dangerous heart rhythm problems, especially in overdose or combined with other QT-prolonging medicines, and it must be kept well out of the reach of children.

Aralen

Chloroquine

250/500mg

Aralen is a antiparasitics medication containing Chloroquine, available as 250/500mg tablets.

from $0.56 / tablet View

Key facts

  • Chloroquine prevents and treats malaria caused by susceptible parasites, and at lower doses is used long-term for lupus and rheumatoid arthritis.
  • For malaria prevention you usually start it one to two weeks before travel and continue for four weeks after leaving the risk area; your prescriber sets the dose for treatment or autoimmune disease.
  • Chloroquine can cause dangerous heart rhythm changes, the risk rises with high doses, existing heart disease, low blood potassium, or other heart-rhythm-affecting medicines, and even a modest overdose can be fatal.
  • Seek urgent care for a fast, irregular or pounding heartbeat, fainting, sudden vision changes, or ringing in the ears.

What chloroquine treats

Chloroquine treats and prevents malaria in regions where the parasite has not developed resistance to it. At lower, long-term doses it also treats systemic lupus erythematosus and rheumatoid arthritis by calming an overactive immune response. It is not a proven treatment for viral infections.

How chloroquine works

Malaria parasites living inside red blood cells break down haemoglobin and must neutralise the toxic byproduct this releases. Chloroquine concentrates inside the parasite and blocks that neutralising process, letting the toxic byproduct build up until it kills the parasite. In lupus and rheumatoid arthritis, chloroquine interferes with signalling inside immune cells, reducing the inflammation those diseases cause.

Before you take it

  • Do not take chloroquine if you have existing retinal or visual field damage, a known allergy to it or related antimalarials, or a heart rhythm disorder with a prolonged QT interval.
  • Tell your prescriber about G6PD deficiency, psoriasis, epilepsy, myasthenia gravis, or liver or kidney disease, chloroquine can worsen each of these.
  • Other medicines that affect heart rhythm, including certain antibiotics, antiarrhythmics and antipsychotics, should not be combined with chloroquine without medical advice.

Side effects

Common effects include nausea, headache, dizziness, itching, and temporary blurred vision.

Stop and seek urgent medical care for any of these:

  • An irregular or pounding heartbeat, or fainting.
  • Sudden vision loss, new blind spots, or persistent visual changes.
  • Ringing in the ears, sudden hearing loss, or muscle weakness.
  • Seizures.

Safety essentials

  • Never exceed your prescribed dose and never combine chloroquine with other medicines known to affect heart rhythm, overdose and drug interactions here can be fatal. Keep it locked away from children, a handful of tablets can kill a small child.
  • If you take chloroquine long-term for lupus or arthritis, you need a baseline and then periodic eye examination, retinal damage from cumulative dosing can become permanent if it is not caught early.
  • Ask about G6PD testing before starting if you have a family history of the deficiency, chloroquine can trigger sudden red blood cell breakdown in affected people.

This page is educational and does not replace advice from a doctor or pharmacist who knows your health history.