Aralen (chloroquine) is a Disease Modifying Anti-Rheumatic Drug (DMARD) that is widely used to reduce inflammation (pain and swelling) in the treatment of many types of arthritis and lupus.

Aralen is also known as a treatment for malaria, a disease caused by a blood-borne parasite and spread by mosquitoes in many tropical and sub-tropical environments.

Taking Aralen

Aralen is available as 250 mg oral tablets. The dose is based on lean body weight.

The usual dose ranges from one-half tablet (125 mg) to one tablet (250 mg) per day. The dose should not exceed 3 mg/kg/day of lean body weight.

It can take 8 to 12 weeks for Aralen to start working. It is important for people starting this medication to continue to take it every day. It can take up to 6 months to feel the maximum effect.

Important Tests and Risks

Annual Eye Checkup

Aralen is generally considered to be safe, but it can very rarely cause issues with the eyes.

Patients who take Aralen should have their eyes checked by an eye doctor at least once a year to make sure the medication isn’t affecting the retina at the back of each eye.


How Aralen Works

It is not well understood how Aralen helps treat autoimmune diseases like lupus and many types of arthritis. It is thought that Aralen interferes with how cells in the immune system communicate with each other.


Side Effects

Aralen is a very well tolerated medication and most patients have no side-effects at all.

People taking Aralen should get their eyes checked by an eye doctor at least once a year to make sure the medicine isn’t affecting the back of the eye.

MORE COMMON side-effects include:

  • Mild nausea, loss of appetite, and occasional stomach cramps.
  • Diarrhea
  • Mild blurry vision at first

RARE side-effects include:

  • Skin rashes including a blue/black discolouration of the skin and worsening of psoriasis. Heightened sensitivity to the sun
  • Headaches or dizziness
  • Nervousness, restlessness, and difficulty sleeping
  • Ringing in the ears (tinnitus)
  • Damage to the Eyes – Aralen can very rarely build up in the back of the eye (retina). This is why it’s important to get an annual eye checkup. The most common symptoms of this side effect are difficulty reading or seeing (words, letters, or parts of objects may be missing) or blurred vision. The toxicity to the retina seems to be related to the daily dose of medication.

Patients should talk to their doctor if they are concerned about any side effects.

Who Should NOT Take Aralen

People who should NOT be taking Aralen include:

  • People who have had a previous reaction to Aralen (chloroquine)
  • People who have had eye problems as a result of Aralen

When to Call a Doctor

People taking Aralen should call their doctor if they feel sick and want to stop, or if they are concerned about any side effects.

Other reasons to call a doctor while taking Aralen include:

  • Development of a rash
  • Feeling sick
  • Ringing in the ears (tinnitus)


Watch rheumatologist Dr. Andy Thompson introduce Aralen in a short 1.5 minute video: