Antimalarial medication is used to prevent and treat malaria.
You should always consider taking antimalarial medicine when travelling to areas where there's a risk of malaria. Visit your GP or local travel clinic for malaria advice as soon as you know when and where you're going to be travelling.
It's very important to take the correct dose and finish the course of antimalarial treatment. If you're unsure, ask your GP or pharmacist how long you should take your medication for.
It's usually recommended you take antimalarial tablets if you're visiting an area where there's a malaria risk as they can reduce your risk of malaria by about 90%.
The type of antimalarial tablets you will be prescribed is based on the following information:
where you're going
any relevant family medical history
your medical history, including any allergies to medication
any medication you're currently taking
any problems you've had with antimalarial medicines in the past
whether you're pregnant
You may need to take a short trial course of antimalarial tablets before travelling. This is to check that you don't have an adverse reaction or side effects. If you do, alternative antimalarials can be prescribed before you leave.
Types of antimalarial medication
The main types of antimalarials used to prevent malaria are described below.
Atovaquone plus proguanil
dosage – the adult dose is one adult-strength tablet a day. Child dosage is also once a day, but the amount depends on the child's weight. It should be started one or two days before your trip and taken every day you're in a risk area, and for seven days after you return.
recommendations – a lack of clear evidence means this antimalarial shouldn't be taken by pregnant or breastfeeding women. It's also not recommended for people with severe kidney problems.
possible side effects – stomach upset, headaches, skin rash and mouth ulcers.
other factors – it can be more expensive than other antimalarials, so may be more suitable for short trips.
Doxycycline (also known as Vibramycin-D)
dosage – the dose is 100mg daily as a tablet or capsule. You should start the tablets two days before you travel and take them each day you're in a risk area, and for four weeks after you return.
recommendations – not suitable for pregnant or breastfeeding women, children under the age of 12 (because of the risk of permanent tooth discolouration), people who are sensitive to tetracycline antibiotics, or people with liver problems.
possible side effects – stomach upset, heartburn, thrush, and sunburn as a result of light sensitivity. It should always be taken with food, preferably when standing or sitting.
other factors – it is relatively cheap. If you take doxycycline for acne, it will also provide protection against malaria as long as you're taking an adequate dose. Ask your GP.
Mefloquine (also known as Lariam)
dosage – the adult dose is one tablet weekly. Child dosage is also once a week, but the amount will depend on their weight. It should be started three weeks before you travel and taken all the time you're in a risk area, and for four weeks after you get back.
recommendations – it's not recommended if you have epilepsy, seizures, depression or other mental health problems, or if a close relative has any of these conditions. It's not usually recommended for people with severe heart or liver problems.
possible side effects – dizziness, headache, sleep disturbances (insomnia and vivid dreams) and psychiatric reactions (anxiety, depression, panic attacks and hallucinations). It's very important to tell your doctor about any previous mental health problems, including mild depression. Don't take this medication if you have a seizure disorder.
other factors –if you haven't taken mefloquine before, it's recommended you do a three-week trial before you travel to see whether you develop any side effects.
Chloroquine and proguanil
A combination of antimalarial medications called chloroquine and proguanil is also available, although these are rarely recommended nowadays because they're largely ineffective against the most common and dangerous type of malaria parasite, Plasmodium falciparum.
However, chloroquine and proguanil may occasionally be recommended for certain destinations where the Plasmodium falciparum parasite is less common than other types, such as India and Sri Lanka.
If malaria is diagnosed and treated promptly, a full recovery can be expected. Treatment should be started as soon as a blood test confirms malaria.
Many of the same antimalarial medicines used to prevent malaria can also be used to treat the disease. However, if you've taken an antimalarial to prevent malaria, you shouldn't take the same one to treat it. This means it's important to tell your doctor the name of the antimalarials you took.
The type of antimalarial medicine and how long you need to take it will depend on:
the type of malaria you have
where you caught malaria
the severity of your symptoms
whether you took preventative antimalarial tablets
whether you're pregnant
Your doctor may recommend using a combination of different antimalarials to overcome strains of malaria that have become resistant to single types of medication.
Antimalarial medication is usually given as tablets or capsules. If someone is very ill, it will be given through a drip into a vein in the arm (intravenously) in hospital.
Treatment for malaria can leave you feeling very tired and weak for several weeks.
Emergency standby treatment
In some cases, you may be prescribed emergency standby treatment for malaria before you travel. This is usually if there's a risk of you becoming infected with malaria while travelling in a remote area with little or no access to medical care.
Examples of emergency standby medications include:
atovaquone with proguanil
artemether with lumefantrine
quinine plus doxycycline
quinine plus clindamycin
Your GP may decide to seek advice from a travel health specialist before prescribing emergency standby treatment.
Read more about emergency treatment for malaria.
Antimalarials in pregnancy
If you're pregnant, it's advisable to avoid travelling to areas where there's a risk of malaria.
Pregnant women have an increased risk of developing severe malaria, and both the baby and mother could experience serious complications.
It's very important to take the right antimalarial medicine if you're pregnant and unable to postpone or cancel your trip to an area where there's a malaria risk.
Some of the antimalarials used to prevent and treat malaria are unsuitable for pregnant women because they can cause side effects for both mother and baby.
The list below outlines which medications are safe or unsafe to use while pregnant:
mefloquine – not usually prescribed during the first trimester of pregnancy, or if pregnancy is a possibility during the first three months after preventative antimalarial medication is stopped. This is a precaution, even though there's no evidence to suggest mefloquine is harmful to an unborn baby.
doxycycline – never recommended for pregnant or breastfeeding women as it could harm the baby.
atovaquone plus proguanil – not generally recommended during pregnancy or breastfeeding because research into the effects is limited. However, if the risk of malaria is high, they may be recommended if there's no suitable alternative.
Chloroquine combined with proguanil is suitable during pregnancy, but it is rarely used as it's not very effective against the most common and dangerous type of malaria parasite.