If you are taking chloroquine to protect against malaria, it is important that you take it exactly as you have been told. Do not miss any doses.

It is one of a number of measures that you need to take to reduce your risk of malaria. Others include wearing suitable clothing, using insect repellents and sleeping in screened rooms or beds.

Take chloroquine one week before you travel, during the whole of your stay, and for four weeks after you return.

Store chloroquine safely out of the reach and sight of children. Chloroquine is harmful in overdose or if ingested accidentally.

About chloroquine

Type of medicine Antimalarial
Used for To prevent malaria
Occasionally used to treat rheumatoid arthritis or lupus erythematosus
Also called Avloclor® (chloroquine phosphate)
Malarivon® (chloroquine phosphate)
Nivaquine® (chloroquine sulfate)
Available as Tablets and liquid medicine

Chloroquine is mainly used to prevent malaria. It can be used on its own or in combination with another antimalarial to increase its effectiveness. It can also be used to treat some forms of malaria.

Malaria is a serious infection. It is common in tropical countries such as parts of Africa, Asia and South America. Malaria is a disease which is passed on to humans by infected mosquitoes. A parasite called plasmodium lives inside the stomachs of infected female mosquitoes and is passed on to humans by a bite.

The pattern of malaria varies with the part of the world you are travelling to, as well as the season and the type of activity you have planned. Because of this, you should always obtain the latest advice about malaria prevention from your doctor, pharmacist or travel organiser. A backpacking trip may well require different preventative measures against malaria to those needed for a business trip to a city.

Chloroquine is not prescribable on the NHS in order to prevent malaria, but you are able to buy the tablets at pharmacies, without a prescription, for this purpose.

Chloroquine is available on prescription to treat rheumatoid arthritis and lupus erythematosus, although other treatments are usually preferred. These are both autoimmune diseases. This means that your immune system (which normally protects your body from infections) mistakenly attacks itself. This causes pain and damage to parts of your body. Chloroquine is used in some people to help reduce the damage caused.

Before taking chloroquine

Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start taking chloroquine it is important that your doctor or pharmacist knows:

  • If you are pregnant, trying for a baby or breast-feeding.
  • If you have kidney or liver problems.
  • If you have epilepsy.
  • If you have psoriasis (this is a skin disorder).
  • If you have myasthenia gravis (this is a condition causing muscle weakness).
  • If you have problems with your stomach or intestines.
  • If you know you have glucose-6-phosphate dehydrogenase (G6PD) deficiency (this is an inherited disorder which causes problems after eating some foods, such as fava beans).
  • If you have porphyria (this is a rare inherited blood disorder).
  • If you are taking any other medicines. This includes any medicines you are taking which are available to buy without a prescription, such as herbal and complementary medicines.
  • If you have ever had an allergic reaction to a medicine.

How to take chloroquine

  • Before you start this treatment, read the manufacturer's printed information leaflet from inside your pack. The leaflet will give you more information about the specific brand of chloroquine you have been given, and a full list of side-effects which you may experience from taking it.
  • It is important that you take chloroquine exactly as your doctor tells you to. Your doctor or pharmacist will tell you how much to take and when to take it. Your dose will also be on the label of the pack to remind you.
  • If you take a medicine for indigestion (such as an antacid), do not take it within 2-3 hours before or after taking chloroquine. This is because antacids interfere with the way chloroquine is absorbed by your body, making it less effective.
  • If you have been advised to have an oral vaccine to protect you against typhoid, you should arrange to have this so your course is finished at least three days before you start taking chloroquine. This is because chloroquine can stop the vaccine from working properly.

If you are taking chloroquine to protect against malaria:

  • Ideally, you should take the first dose of chloroquine a week before you are due to travel. This is to ensure there is sufficient medicine in your bloodstream to give you the required protection. If you are unable to take it a week beforehand, take your first dose as soon as possible but this must be at least 1-2 days before you travel. You should continue to take chloroquine throughout your stay and for a further four weeks after you have left the area.
  • Take the tablets (or medicine) exactly as your doctor or pharmacist has told you. The dose for an adult is two tablets once a week, on the same day of the week. If it is for a child, read the directions on the label carefully, as the dose will depend upon their age and weight.
  • If you forget to take a dose, take it as soon as you remember and then wait seven days before you take your next dose.
  • You should complete the course of tablets (or medicine), unless you are told otherwise by a doctor. This means making sure you remember to take chloroquine for four weeks after your visit is over.
  • Chloroquine will help prevent you from getting malaria, but it is also important that you take the following precautions against being bitten by mosquitoes:
    • Cover up bare areas of your arms and legs with long-sleeved, loose-fitting clothing, long trousers and socks. This is especially important if you are outside after sunset, as this is when mosquitoes feed.
    • Use an effective insect repellant spray on your clothing and any area of your skin which is bare.
    • Spray the room with an insecticide each evening a couple of hours before you go to bed. Check your sleeping areas for mosquitoes - pay particular attention to furniture and areas under your bed where insects can hide.
    • If you are sleeping in an unscreened room, use a mosquito net impregnated with an insecticide.
  • If you feel ill or develop a fever or flu-like symptoms while you are travelling or within one year of returning home, you should see your doctor straightaway. This is important, even if you have taken your antimalarial correctly.

If you are taking chloroquine for rheumatoid arthritis or lupus erythematosus

  • It is usual to take chloroquine daily. The dose will be adjusted to suit you, so your doctor or specialist will tell you how much you should take; for most people this is likely to be one tablet daily. Your dose will be printed on the label of the pack to remind you.
  • Try to keep your regular appointments with your doctor. This is so your doctor can check on your progress. Your doctor is likely to check your vision before you start this treatment, and then once every year. This is because chloroquine can affect your eyesight when taken over a long period of time. If you notice any changes in your vision, you should inform your doctor as soon as possible.
  • If you forget to take a dose, take it as soon as you remember. If you do not remember until the following day, skip the missed dose. Do not take two doses together to make up for a forgotten dose.

Can chloroquine cause problems?

All medicines can cause unwanted side-effects along with their useful effects. These usually improve as your body adjusts to the new medicine. When chloroquine is used to prevent malaria, side-effects are generally uncommon and not serious. Where chloroquine is taken for a long time, side-effects may be more serious. Speak with your doctor or pharmacist if any of the following continue or become troublesome:

Possible chloroquine side-effects
What can I do if I experience this?
Feeling or being sick, diarrhoea Stick to simple foods - avoid spicy or rich foods
Headache Ask your pharmacist to recommend a suitable painkiller
Feeling dizzy or light-headed Do not drive or use tools or machines until the feeling passes
Loss of hair, changes in skin colour, itchy skin rash If any of these become troublesome, speak with your doctor

If you experience any other symptoms which you think may be due to this medicine, speak with your doctor or pharmacist.

How to store chloroquine

  • Keep all medicines out of the reach and sight of children. Chloroquine is harmful in overdose or if ingested accidentally.
  • Store in a cool, dry place, away from direct heat and light.