Chloroquine (By mouth)

Chloroquine (KLOR-oh-kwin)

Prevents and treats malaria. Also treats extraintestinal amebiasis (liver infection).

Brand Name(s):

There may be other brand names for this medicine.

When This Medicine Should Not Be Used:

This medicine is not right for everyone. Do not use it if you had an allergic reaction to chloroquine or similar medicines. This medicine may increase your risk of heart rhythm problems (including QT prolongation, ventricular fibrillation, ventricular tachycardia). Do not take any medicine that contains chloroquine unless prescribed by your doctor.

How to Use This Medicine:

Tablet

  • Take your medicine as directed. Your dose may need to be changed several times to find what works best for you. If you take this medicine only once a week, always take it on the same day of each week.
  • Malaria prevention while traveling: You may need to start using this medicine 2 weeks before you start your trip. You may also need to keep using this medicine for 8 weeks after you get home. Ask your doctor about your schedule.
  • Take all of the medicine in your prescription to clear up your infection, even if you feel better after the first few doses.
  • Missed dose:
    • If you take your medicine once every 7 days, take the missed dose as soon as you can, then wait 7 days before taking another dose.
    • If you take your medicine every day, take the missed dose as soon as you can. If it is almost time for your next regular dose, wait until then to take your medicine and skip the missed dose.
  • Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

  • Some medicines can affect how chloroquine works. Tell your doctor if you are using any of the following:
    • Azithromycin, cimetidine, cyclosporine, mefloquine, praziquantel, tamoxifen
    • Insulin or other diabetes medicine
    • Medicine to treat heart rhythm problems
  • Tell your doctor if you need a rabies vaccine.
  • Take antacids or kaolin at least 4 hours before or after taking this medicine.
  • Take ampicillin at least 2 hours before or after taking this medicine.

Warnings While Using This Medicine:

  • Tell your doctor if you are pregnant or breastfeeding, or if you have kidney disease, liver disease, heart disease, blood disorders (including porphyria, G6PD deficiency), psoriasis, hearing problems, or a history of epilepsy or heart rhythm problems. Tell your doctor if you drink alcohol.
  • Tell your doctor if you have had eye or vision problems caused by chloroquine or similar drugs.
  • This medicine may cause the following problems:
    • Heart problems
    • Low blood sugar, which could be life-threatening
    • Changes in heart rhythm, including QT prolongation
    • Changes in vision, eye damage
    • Muscle and nerve problem
    • Increased risk of seizures
  • Call your doctor if your symptoms do not improve or if they get worse.
  • Your doctor will do lab tests at regular visits to check on the effects of this medicine. Keep all appointments.
  • Keep all medicine out of the reach of children. Never share your medicine with anyone.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
  • Changes in vision, trouble seeing, light flashes
  • Fast, pounding, or uneven heartbeat
  • Increased hunger, headache, confusion, shaking, trembling, sweating
  • Lightheadedness, dizziness, fainting
  • Seizures
  • Swelling in your hands, ankles, or feet
  • Trouble breathing, cold sweat, bluish-colored skin
  • Trouble hearing, ringing in the ears
  • Twitching or muscle movements you cannot control, problems with balance or walking, muscle weakness
  • Unusual bleeding, bruising, or weakness

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088


Last Updated: 9/6/2024

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