chloroquine phosphate at a glance
Medicine class
Aminoquinoline antimalarial.
Main role
Prevention, suppression and treatment of malaria caused by chloroquine-susceptible parasites.
Resistance
Chloroquine resistance is widespread, particularly in falciparum malaria.
Administration
Taken by mouth; Avloclor tablets should be swallowed after food.
What is chloroquine phosphate used for?
Licensed uses for the selected products include:
Prevention and suppression of malaria.
Treatment of malaria caused by susceptible parasites.
Avloclor tablets: amoebic hepatitis or liver abscess.
Avloclor tablets: discoid or systemic lupus erythematosus.
Avloclor tablets: rheumatoid arthritis.
How does chloroquine phosphate work?
Chloroquine accumulates inside the malaria parasite’s acidic digestive compartment. It disrupts handling of haem released during haemoglobin digestion, allowing toxic material to build up and damage susceptible blood-stage parasites.
How to take chloroquine phosphate
Follow the product leaflet and instructions from the prescriber or pharmacist because administration varies by indication and formulation.
Take Avloclor tablets after food and swallow them with water.
Measure Malarivon syrup carefully with an appropriate measuring device.
Do not interchange tablet and syrup quantities because their chloroquine-base content differs.
Antacids containing aluminium, calcium or magnesium and adsorbents such as kaolin can reduce absorption; ask a pharmacist how to separate them from chloroquine.
Continue mosquito-bite precautions because no antimalarial provides complete protection.
Do not drive or operate machinery if blurred or double vision occurs.
chloroquine phosphate side effects
Common or expected effects
- Nausea, vomiting, diarrhoea or abdominal discomfort
- Headache
- Itching or rash
- Difficulty sleeping
- Temporary blurred vision or difficulty focusing
Get urgent medical advice
- Severe allergic reaction or angioedema
- Severe blistering, peeling or widespread rash
- Abnormal heart rhythm, QT prolongation or cardiomyopathy
- Seizures
- Severe hypoglycaemia, including loss of consciousness
- Persistent sight, visual-field or colour-vision changes
- Marked psychiatric or behavioural changes, including suicidal thoughts
- Serious blood, liver, muscle or hearing disorders
chloroquine phosphate in pregnancy
Chloroquine can be used during pregnancy when a clinician considers it the best option for preventing or treating malaria; malaria itself poses substantial risks to the woman and baby. Travel to malaria-risk areas should ideally be avoided during pregnancy. Specialist review is particularly important for prolonged high-exposure use or non-malarial indications.
chloroquine phosphate while breastfeeding
Use for malaria prevention is considered compatible with breastfeeding, but the amount in milk cannot protect the infant; the baby needs a separate malaria risk assessment. Breastfeeding is not recommended during prolonged high-exposure Avloclor treatment for rheumatic disease.
chloroquine phosphate interactions
Check all prescribed, non-prescribed and herbal products before use. Important interactions include:
Amiodarone
Concomitant use is contraindicated because of the risk of serious cardiac arrhythmia.
Other QT-prolonging medicines
Some antiarrhythmics, antipsychotics, antidepressants and anti-infectives may increase ventricular-arrhythmia risk.
Macrolide antibiotics
Azithromycin, clarithromycin and erythromycin may increase cardiovascular risk.
Common questions about chloroquine phosphate
Answers are fully visible for fast scanning and source review.
Does chloroquine phosphate prevent malaria everywhere?
No. Chloroquine-resistant falciparum malaria is widespread, so suitability depends on the destination and an individual travel-health assessment.
Can it treat malaria after symptoms begin?
It is licensed for malaria caused by susceptible parasites, but suspected malaria needs urgent testing and specialist treatment because resistance and disease severity affect medicine choice.
Can it be used during pregnancy?
Yes, when a clinician decides it is the best option for malaria prevention or treatment. Malaria itself can be life-threatening during pregnancy.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.