Guidance

Special risk groups

Updated 17 June 2026

Pregnancy

Pregnant women are advised to avoid travel to malarious areas.

Pregnant women have an increased risk of developing severe malaria and a higher risk of fatality compared to non-pregnant women.

If travel is unavoidable, the pregnant traveller should be informed of the risks which malaria presents and the risks and benefits of antimalarial chemoprophylaxis.

Diagnosis of falciparum malaria in pregnancy can be particularly difficult, as parasites may not be detectable in blood films due to sequestration in the placenta. Placental examination for parasites is recommended in all women who have malaria infection diagnosed during pregnancy.

Expert advice is required at an early stage if malaria is suspected in a pregnant woman. Complications, including severe anaemia, hypoglycaemia, jaundice, renal failure, hyperpyrexia and pulmonary oedema, may ensue. The result may be miscarriage, premature delivery, maternal and/or neonatal death.

Congenital malaria is rare but occurs more commonly with P. vivax than with the other malaria parasites of humans.

Avoidance of mosquito bites is extremely important in pregnancy as pregnant women are particularly attractive to mosquitoes. Ideally, pregnant women should remain indoors between dusk and dawn. If they must be outdoors at night they should adhere rigorously to bite precautions (see Bite prevention).

DEET should be used in a concentration of not more than 50%. DEET has a good safety record in children and pregnancy (36) but ingestion should be avoided. Women who are breastfeeding should wash repellents off their hands and breast skin prior to handling infants. See Bite prevention for further details on DEET.

Chloroquine

Chloroquine is safe in all trimesters of pregnancy. Its major disadvantage is the relatively poor protection it gives in many geographical areas due to the presence of drug-resistant P. falciparum.

Mefloquine

Caution in first trimester but can be used in all trimesters for travellers to high risk areas. It seems unlikely that mefloquine is associated with adverse fetal outcomes (89, 90, 91).

A review of the manufacturer’s global drug safety database covering 1986 to 2010 showed that for mefloquine exposure in pregnancy, the birth defect prevalence and fetal loss in maternal, prospectively monitored cases were comparable to background rates (94).

The decision whether to advise mefloquine prophylaxis in pregnancy always requires a careful harm-benefit analysis. Where the levels of transmission and drug resistance (see the country tables in Country recommendations) make mefloquine an agent of first choice, it is generally agreed that mefloquine may be used in the second and third trimesters of pregnancy.

Given the potential severity of falciparum malaria in a pregnant woman, its use is also justified in the first trimester in areas of high risk of acquiring falciparum malaria such as sub-Saharan Africa (see Information resources).

Women who have taken mefloquine inadvertently just prior to or during the first trimester should be advised that this does not constitute an indication to terminate the pregnancy (95).

Doxycycline

This is generally avoided in pregnancy. However, if required before 15 weeks’ gestation it should not be withheld if other options are unsuitable. The course of doxycycline, including the 4 weeks after travel, must be completed before 15 weeks’ gestation (63).

Atovaquone/proguanil

There is a lack of evidence on the safety of atovaquone-proguanil in pregnancy. Animal studies showed no evidence for teratogenicity of this combination. The individual components have shown no effects on parturition or pre- and post-natal development (Malarone SmPC).

A registry-based study of the inadvertent use of atovaquone-proguanil in weeks 3 to 8 after conception identified 149 pregnancies and found no significant association between exposure to atovaquone-proguanil in early pregnancy and the risk of a major birth defect (80).

An anonymous, internet-based survey to describe outcomes of pregnancies accidentally exposed to atovaquone-proguanil identified 10 who had atovaquone–proguanil exposure in the first trimester. All resulted in term births with no birth defects (80).

A study of 198 women who received atovaquone-proguanil in pregnancy or breastfeeding (79.8% of them in the first trimester) did not show a specific signal to suggest a teratogenic effect, but numbers were too small confidently to determine safety of this combination in pregnancy (96).

A systematic review of the safety of atovaquone-proguanil for malaria prevention and treatment in pregnancy suggested that the rates of adverse events are not higher than the expected rates in similar populations (97).

A retrospective analysis of risk for adverse foetal and infant outcomes after atovaquone-proguanil exposure in pregnancy was unable to reach a definitive conclusion but highlighted a clear need for further research (98).

The use of other agents, rather than atovaquone plus proguanil (AP) combination preparation, is usually advised in pregnancy. However, the UK Malaria Expert Advisory Group (UKMEAG) advises that if there are no other appropriate options, it may be used in pregnancy. The co-prescription of folic acid (5mg daily) is advised alongside AP if conception is planned and in all trimesters of pregnancy. This is particularly relevant for use in the first trimester because of a theoretical increased risk of neural tube defects related to the antifolate action. The individual components have shown no adverse effects on parturition (childbirth) or pre- and post-natal development and animal studies show no evidence for teratogenicity.

Folic acid 5mg daily should be taken for the length of time that atovaquone/proguanil is taken in pregnancy and also by those taking atovaquone/proguanil who are seeking to become pregnant.

Women who have taken AP inadvertently just prior to or during the first trimester should be advised that this does not constitute grounds to terminate the pregnancy, as no evidence of harm has emerged in data so far available (80, 81).

For a useful recent review of malaria in the pregnant traveller see reference (99).

The decision whether to advise prophylaxis in pregnancy always requires a careful harm-benefit analysis. Summary recommendations on chemoprophylaxis use during pregnancy are available in table 8.

Table 8. Summary recommendations on chemoprophylaxis use during pregnancy

Drug	Use during pregnancy
Atovaquone/Proguanil	Not routinely advised due to sparse data. However, if there are no other appropriate options, its use may be used in all trimesters of pregnancy. The co-prescription of folic acid (5mg daily) is advised alongside AP if conception is planned and in all trimesters of pregnancy. This is particularly relevant for use in the first trimester, because of a theoretical increased risk of neural tube defects related to the antifolate action. The individual components have shown no adverse effects on parturition (childbirth) or pre- and post-natal development and animal studies show no evidence for teratogenicity.
Chloroquine	Safe in all trimesters of pregnancy
Doxycycline	Should be avoided, but before 15 weeks’ gestation it should not be withheld if other options are unsuitable. The course, including the 4 weeks after travel, must be completed before 15 weeks’ gestation
Mefloquine	Caution in first trimester but can be used in all trimesters for travellers to high risk areas.

Chemoprophylaxis prior to conception

If a female traveller is planning to conceive during a visit to a destination with a high risk of contracting chloroquine-resistant falciparum malaria, expert advice should be sought.

Those travellers who plan to become pregnant after taking antimalarials and who wish to do so with minimal antimalarial drug present, may elect to observe the following time intervals after completing the course, before attempting to conceive:

• Mefloquine – 3 months
• Doxycycline – 1 week
• Atovaquone/proguanil – 2 weeks

Breastfeeding

Breastfeeding mothers should be advised to take the usual adult dose of antimalarial appropriate for the country to be visited.

The amount of medication in breast milk will not protect the infant from malaria. Therefore, the breastfeeding child needs their own prophylaxis. See tables 3 to 5 in Chemoprophylaxis.

Mefloquine

Experience suggests mefloquine is safe to use during breastfeeding.

Doxycycline

The British National Formulary (BNF) states that tetracyclines should not be given to women who are breastfeeding (64). While use during breastfeeding is contraindicated in the SmPC and BNF (64), a Centers for Disease Control and Prevention (CDC) expert meeting on malaria chemoprophylaxis stated that doxycycline is excreted at low concentrations in breast milk and that the American Academy of Pediatrics (AAP) assessed tetracycline as compatible with breastfeeding (65).

The UKMEAG’s view is that other options are preferable in those who are breastfeeding, but doxycycline can be used if other options are unsuitable. Courses longer than a month should be avoided wherever possible.

Atovaquone/proguanil

The UKMEAG advises that atovaquone-proguanil can be used when breastfeeding if there is no suitable alternative antimalarial.

Table 9. Chemoprophylaxis recommendations during breastfeeding

Drug	Use in breastfeeding
Atovaquone/Proguanil	Not recommended however, can be used if there is no suitable alternative antimalarial.
Chloroquine	Safe to use
Doxycycline	Not recommended however, can be used if there is no suitable alternative antimalarial.
Mefloquine	Experience suggests safe to use.

Anticoagulants

The coumarins, including warfarin

Travellers using an anticoagulant should ensure their INR (International Normalised Ratio) is stable and within the therapeutic range prior to departure and they have adequate supplies of their anticoagulant for the whole trip. Changes in diet and alcohol intake can affect the INR.

Patients on warfarin may have underlying cardiovascular disease and may be on cardiovascular medication. Interactions with other medication together with the individual’s medical history should be taken into account when deciding on appropriate malaria chemoprophylaxis, and the BNF and SmPC should be consulted for the latest information before prescribing.

Chloroquine

No interaction between warfarin and chloroquine documented in the BNF.

Mefloquine

Not considered to be a problem for those taking warfarin. The manufacturer states that: “the effects of mefloquine on travellers receiving co-medication, particularly those on anticoagulants or antidiabetics, should be checked before departure”. See below for how this can be monitored.

Doxycycline

Doxycycline increases the anticoagulant effect of warfarin and the manufacturer advises monitoring the INR (64).

Atovaquone/proguanil

There have been isolated reports of an enhanced effect of warfarin when taken together with proguanil, a component of this combination preparation (100). The INR should be monitored (see below)

Table 10. Chemoprophylaxis and interaction with coumarins including warfarin

Drug	Interaction with coumarins including warfarin
Atovaquone/proguanil	There have been isolated reports of an enhanced effect of warfarin when taken together with proguanil, a component of this combination preparation (100)
Chloroquine	No interaction between warfarin and chloroquine is documented in BNF
Doxycycline	Doxycycline increases the anticoagulant effect of warfarin and the manufacturer advises monitoring the INR (64)
Mefloquine	Not considered to be a problem for those taking warfarin. “The effects of mefloquine on travellers receiving co-medication, particularly those on anticoagulants or antidiabetics, should be checked before departure”

Advice for travellers needing malaria chemoprophylaxis who are taking warfarin

Travellers should inform their anticoagulant clinic and start taking their malaria tablets 2 to 3 weeks prior to their departure.

A baseline INR should be checked prior to starting chemoprophylaxis and re-checked after one week of taking chemoprophylaxis to determine whether the warfarin dosage needs to be adjusted. The traveller should check with their anticoagulant clinic to see if their INR is appropriate for travel. If a traveller is away for a long period of time the INR should be checked at intervals at the destination. However, the sensitivity of thromboplastin reagent used by some laboratories in different countries may vary (101). Self-monitoring of the INR may be suitable for some travellers but should be under the supervision of an anticoagulant clinic (102). INR self- testing devices are readily available and can be used safely by experienced patients. Expert patients, defined as such by their anticoagulant clinic, can undertake self-management. Other patients may perform INR self-testing and stay in contact with their home anticoagulant clinic for dosage recommendations (102). Given modern communication methods it should be possible to keep-in touch from many malaria-endemic areas.

Once chemoprophylaxis has been completed, the INR should be checked again to re-stabilise anticoagulant therapy.

Direct oral anticoagulants (DOAC)

Dabigatran etexilate, rivaroxaban, apixaban and edoxaban are the most commonly available direct oral anticoagulants (DOAC). They do not interact with food, do not usually require laboratory monitoring and have a lower potential for drug interactions than the coumarins (see below) (103, 104, 105).

There is relatively limited experience of antimalarial chemoprophylactic use by those taking DOAC.

Apixaban and rivaroxaban are substrates of CYP3A4 and p-glycoprotein. Dabigatran is a substrate of p-glycoprotein.

Mefloquine inhibits CYP3A4 and p-glycoprotein, so could increase DOAC plasma concentrations which might lead to an increased bleeding tendency (105).

Atovaquone may produce minor inhibition of CYP3A4. The effect of proguanil on this enzyme is unknown.

Neither atovaquone nor proguanil inhibits p-glycoprotein (105).

In addition to following this guideline, please consult the drug interactions section of the latest edition of the BNF and the product SmPCs. If doubt exists after taking these steps, seek expert advice from a haematologist.

Epilepsy

A history of febrile convulsions only does not contraindicate use of any of the currently available malaria chemoprophylactic drugs. Table 11 below provides advice on chemoprophylaxis for travellers with epilepsy where restrictions do apply.

Table 11. Chemoprophylaxis for travellers with epilepsy

Drug	Use in epilepsy
Atovaquone/proguanil	Can be used
Chloroquine	Contraindicated
Doxycycline	Can be used - avoid with phenytoin, carbamazepine, and barbiturates as half-life may be reduced.  If not possible or acceptable to the traveller, increase the dose of doxycycline to 100mg twice daily and counsel regarding measures to minimise the risk of adverse events.
Mefloquine	Contraindicated

Glucose 6-phosphate dehydrogenase deficiency

Glucose 6-phosphate dehydrogenase (G6PD) is an enzyme that helps protect red blood cells against oxidative damage. Absence of G6PD renders red blood cells liable to haemolysis in the presence of some drugs. 

The most common G6PD deficiency allele in Africa (G6PD A-) has been found to provide some protection against infection with malaria (106). However, all G6PD-deficient travellers to malarious areas should take appropriate chemoprophylaxis as described below.

Chloroquine

There is a theoretical risk of haemolysis in some G6PD-deficient individuals. Haemolysis does not appear to be a problem when chloroquine is given in the dose recommended for malaria chemoprophylaxis. A systematic review found low-to-no risk of acute hemolytic anemia for individuals with G6PD deficiency who take hydroxychloroquine or chloroquine (107) so there is no need to withhold chloroquine prophylaxis from those known to be G6PD-deficient.

Primaquine

Not currently recommended as a first line agent for malaria prevention in UK travellers, but primaquine may be considered in special circumstances on expert advice (50). There is a definite risk of haemolysis in G6PD-deficient individuals. The traveller’s G6PD level must be checked before primaquine is prescribed: G6PD deficiency contraindicates its use for prophylaxis.

Table 12. Chemoprophylaxis recommendations in travellers with G6PD deficiency

Drug	Use in G6PD deficiency
Atovaquone/proguanil	Can be used
Chloroquine	Theoretical risk of haemolysis in some G6PD-deficient individuals. Haemolysis does not appear to be a problem when given in the dose recommended for malaria chemoprophylaxis so may be used.
Doxycycline	Can be used
Mefloquine	Can be used

Sickle cell disease and thalassaemia

Presence of the sickle cell trait confers some protection against malaria, though individuals with the sickle cell trait still require antimalarial prophylaxis (108).

For those with homozygous sickle-cell disease, malaria is regarded as a significant cause of morbidity and mortality, producing further haemolysis against the background of that due to sickle cell disease itself. Therefore, it is essential that individuals with sickle cell disease travelling to malaria-endemic areas receive rigorous antimalarial protection.

Thalassaemia may provide protection against severe malaria, but there is currently no evidence it prevents uncomplicated malaria.

Immunocompromised travellers

Risks for transplant patients

A review on the prevention of infection in adult travellers after organ transplantation (109) recommended that ciclosporin levels should be monitored if chloroquine is co-administered.

Risks for those living with HIV

Co-infection with malaria and human immunodeficiency virus (HIV) increases both the severity and mortality rates of those diseases. Most reported studies of malaria and HIV co-infection have been done in those living in endemic areas where HIV infection increases the risks for contracting and developing severe malaria and increasing immunosuppression reduces treatment success (110) although this varies by area (111). A meta-analysis of the co-infection literature covering the years 1991 to 2018 showed a pooled prevalence of severe malaria of 43% in co-infected patients. The odds of severe malaria were significantly higher in HIV and malaria co-infected patients than in malaria mono-infected patients, and significantly higher in children than adults. Furthermore, parasite densities were higher in co-infected patients with severe malaria than those with malaria mono-infection (112). Twenty-eight of the 29 studies in that meta-analysis were conducted in malaria-endemic areas, but one was performed on imported malaria in France, also showing that severe malaria in those living with HIV was associated with decreased CD4 cell counts (113).

Mirzohreh and colleagues (114) reported a systematic review and meta-analysis of malaria prevalence studies in children, pregnant women, and adults living with HIV conducted predominantly in Africa in the period 1983 to 2020. In adult patients living with HIV, CD4+ counts less than 200 cells per microlitre (µl) were associated with a significant increase in the odds of malaria infection, whilst antiretroviral therapy (ART) was associated with a significant decrease in the chance of malaria infection in adults living with HIV.

In pregnant women living with HIV, a CD4+ cell count less than 200 cells/µl is related to a higher risk of malaria infection (114).

Co-infected pregnant women are at risk from higher parasite density, anaemia and malarial infection of the placenta and children born to women living with HIV and malaria infection have low birth weight and are more likely to die during infancy. Data on the effect of malaria during pregnancy on the risk of mother to child transmission of HIV in the pre-ART era were conflicting and have been limited since the widespread use of ART to prevent vertical transmission (115).

In almost all studies on co-infection with HIV, the malaria parasite has been P. falciparum, so data on the interaction with other malarias has been limited. A study from the Brazilian Amazon (116) stated that individuals living with HIV had a significantly greater chance of acquiring Plasmodium vivax malaria than those who were not.

The recommended malaria chemoprophylactic agents are the same for those living with HIV and those who are not infected. Whilst co-trimoxazole has been shown to reduce malaria in adults living with HIV in Africa, it is not as effective as antimalarial chemoprophylactic drugs, so travellers living with HIV should not rely on co-trimoxazole alone for prophylaxis against malaria (115).

The main issue with antimalarial chemoprophylaxis in those living with HIV is the possibility of drug interaction with antiretroviral agents. HIV protease inhibitors (PIs) and the non-nucleoside reverse transcriptase inhibitors (NNRTIs) can either inhibit or induce the same liver enzymes which metabolise most drugs used for malaria prophylaxis and treatment. Potentially this could result in altered metabolism of some antimalarials, though the extent of this and the clinical significance is often unclear, as data is limited. Doxycycline is the simplest chemoprophylaxis against malaria for most people on antiretrovirals.

Nevertheless, the travel health advisers should check the manufacturer’s summary of product characteristics (SmPC) and the BNF on an individual agent basis and should discuss and agree their recommendation for chemoprophylaxis with the traveller’s own HIV physician.

Up-to-date information can also be obtained from the University of Liverpool website where it is possible to look up specific antiretroviral compounds against malaria prophylactic drugs in readily-accessible tables.

Liver disease

Most antimalarial drugs are excreted or metabolised by the liver, therefore there is a risk of drug accumulation in severe liver impairment. A summary of chemoprophylaxis recommendations in travellers with liver disease is available in Table 13 below

Severe liver disease

A CDC expert meeting concluded that the dose of doxycycline does not have to be adjusted in patients with impaired hepatic function since it is excreted as an inactive chelated product via a process of back diffusion in the small bowel (65).

Note to prescribers: The BNF states that tetracyclines should be used with caution in patients with hepatic impairment. The SmPC for atovaquone-proguanil combination preparation states that although no pharmacokinetic studies have been conducted in severe hepatic impairment, no special precautions or dosage adjustment are anticipated.

Mefloquine is contraindicated in severe hepatic impairment (SmPC).

Moderate impairment

Doxycycline, or atovaquone-proguanil combination preparation, or mefloquine may be used.

Mild impairment

Chloroquine, or atovaquone-proguanil combination preparation, or mefloquine or doxycycline may be used.

The choice of chemoprophylaxis should be made after discussion with the patient’s specialist, who will be able to assess their degree of hepatic impairment.

The Child-Pugh classification is often used for grading liver function and can be found at the Liverpool Medics website or the US Department of Veteran Affairs website.

Table 13. Chemoprophylaxis recommendations in travellers with liver disease

Drug	Mild Liver disease	Moderate liver disease	Severe liver disease
Atovaquone/Proguanil	Can be used	Can be used	Manufacturer states that although no pharmacokinetic studies have been conducted in severe hepatic impairment, no special precautions or dosage adjustment are anticipated (SmPC)
Chloroquine	Can be used	Contraindicated	Contraindicated
Doxycycline	Can be used	Can be used	Caution, but dose does not have to be adjusted (see below)
Mefloquine	Can be used	Can be used	Contraindicated (SmPC)

Renal impairment

A summary of chemoprophylaxis recommendations in travellers with renal disease is available in Table 14, below.

Dose reduction for prophylaxis is required only in severe renal impairment.

Atovaquone/proguanil

Atovaquone/proguanil is not recommended for patients with an eGFR of less than 30 mL/minute (64). Not to be used in patients receiving renal dialysis

Doxycycline

Doxycycline may be used in severe renal failure.

Mefloquine

Mefloquine may be used in severe renal failure. There is no need to reduce the dose of mefloquine in renal dialysis (64).

Table 14. Chemoprophylaxis recommendations in travellers with renal disease

Drug	Use in renal disease
Atovaquone/proguanil	Not recommended if eGFR of less than 30 mL/minute (64). Not to be used if receiving renal dialysis.
Chloroquine	Chloroquine is partially excreted via the kidneys - dose reduction for prophylaxis is required only in severe renal impairment.
Doxycycline	May be used in severe renal impairment
Mefloquine	May be used in severe renal impairment - no need to reduce the dose of mefloquine in renal dialysis (64)

Splenectomy

Those who have no spleen or whose splenic function is severely impaired are at particular risk of severe malaria and, where possible, should avoid travel to malarious areas.

If travel is essential, every effort should be made to avoid infection by rigorous use of antimosquito precautions and strict adherence to appropriate chemoprophyaxis, even in BA only malarious areas, apart from those areas regarded as very low to no malaria risk, where BA only would still apply. If the traveller becomes unwell during or after their visit, medical attention is required as a matter of urgency, as malarial parasitaemia in asplenic individuals may rise rapidly to very high levels (for example, greater than 50% with P. falciparum).

The porphyrias

The UK Porphyria Medicines Information Service (UKPMIS), part of the Welsh Medicines Advice Service, has produced guidance on travel and antimalarials for people with acute porphyria.

For travellers who have non-acute (cutaneous) porphyrias, or undiagnosed bullous dermatosis, individual advice should be sought from the UKPMIS.

Children

Children with malaria may deteriorate very rapidly to become critically ill. Those looking after children on their return from malarious areas including: family members, friends, professional carers, or school nursing and medical staff should be made aware that such children need medical attention and a blood test for malaria without delay if they become unwell within a year of leaving a malarious area.

Healthcare professionals should strive to improve access to advice on malaria prevention for families with children, especially travellers visiting friends and relatives (see the Visiting friends and relatives section in Special categories for travel) (117).

Children are at particular risk of severe and fatal malaria; therefore, parents are advised against taking infants and young children to malarious areas without adequate precautions.

Mosquito bite avoidance is extremely important for this age group. If travel is unavoidable, infants and children should be well protected against mosquito bites and receive appropriate malaria chemoprophylaxis.

It is important that the child’s carers understand the importance of trying to ensure that the child properly completes the full course of prophylactic medication. One of the main challenges in giving malaria tablets to babies and young children will be the practical aspects of administration.

Parents should supervise children’s chemoprophylaxis, as some regimens can be difficult even for adults to follow.

Parents should be cautious not to exceed maximum recommended doses, since antimalarials can be particularly toxic to children.

Paediatric doses of antimalarials for prophylaxis are shown in tables 3 to 5 in Chemoprophylaxis, and in the BNF for Children (BNFC). The dose for children will be dependent on the weight and age of the infant or child. Weight is a better guide than age.

A useful antimalarial dosage chart for children can also be downloaded from TravelHealthPro.

Chloroquine

Take care to ensure that tablets are swallowed, as they have a bitter taste. Store safely away from children since an overdose can be fatal.

Chloroquine can be given from birth and is available as sweetened syrup.

The dose steps for chloroquine syrup are not the same as for chloroquine tablets and a child may be prescribed a different dose of chloroquine depending on whether they take tablets or syrup (see tables 3 and 4 in Chemoprophylaxis). The main reason for any differences is due to the different amount of chloroquine base within the syrup and the tablets. The chloroquine syrup formulation contains 50mg chloroquine base/5ml syrup (equivalent to 80mg per 5 ml of chloroquine phosphate, see BNF). The amount of chloroquine base contained within the tablets is 155 mg per tablet (equivalent to 250mg of chloroquine phosphate, see BNF).

The tables in Chemoprophylaxis have been calculated based on weight and surface area and the most accurate dose according to the weight is recommended. Although differences occur, all recommended dosages in the tables fall within accepted limits of toxicity. It is important not to overdose children with chloroquine as severe toxicity can occur.

A practical approach when calculating children’s dosages for chloroquine is to decide on the most appropriate preparation (either tablet or syrup) for the child and calculate the dose appropriate to that preparation, according to tables 3 to 5 in Chemoprophylaxis.

Weight is a better guide than age for children, so they should be weighed for dosage calculation.

Mefloquine

Mefloquine can be given to infants weighing 5kg or more.

There is a problem in administering correct dosage because there is currently no suspension available and adult-dose tablets must be broken.

Doxycycline

Doxycycline is unsuitable for children under 12 years.

Only licensed in the UK for children over the age of 12 years due to its potential to cause bone damage and discolouration of teeth; this age limit varies between countries. Tablets or capsules should be swallowed whole and must not be crushed. Doxycycline is also available in the UK as 100mg dispersible tablets.

Atovaquone-proguanil combination preparation

Atovaquone/proguanil can be given to infants weighing 5kg or more. Paediatric tablets are available.

Paediatric tablets are licensed in the UK for malaria prophylaxis in children from 11kg upwards. For children weighing less than 11kg, the UKMEAG recommends a dosage regimen of:

• weight 5 to 7.9kg – half a paediatric tablet daily
• weight 8 to 9.9kg – three-quarters of a paediatric tablet daily

While it is preferable to avoid breaking and crushing tablets, and in the absence of syrup preparations, the appropriate dose of mefloquine or atovaquone-proguanil combination preparation may be broken if dosing requires it and the drugs crushed if necessary and mixed with condensed milk, butter, oily spreads, full fat pasteurised yoghurt, jam, honey, or similar food to mask the bitter taste, to aid administration to young children.

Goodyer (personal communication) assessed the dosing accuracy obtained when cutting Malarone paediatric tablets. When carers or pharmacists were asked to cut tablets into quarters, the results suggested that only 25% of quarters would be within 10% of the expected weight. Furthermore, there was evidence of an uneven distribution of atovaquone through the tablet mass.

To minimise dose variation, when quarter tablets are required, each quarter from the same tablet should be taken on consecutive days; when half tablets are required, each half from the same tablet should be taken on consecutive days; and if the dose is three-quarters of a tablet, cutting 3 tablets into quarters in advance (total 12) and then giving 3 of the quarter tablets per day can provide 4 days’ dosage and ensure that the correct dose is achieved as smoothly as practicable over that time period.

Tablet-cutters can be purchased from some pharmacies or travel shops. If further advice is required a pharmacist should be consulted.

Elderly travellers

The elderly are at particular risk of dying from malaria once acquired (85). No reduction in antimalarial dosage is required on the basis of advanced age. However, elderly travellers are more likely to have underlying disorders, for example, renal impairment, which may necessitate antimalarial dose reduction. Furthermore, the increased likelihood of elderly travellers taking additional medication, for example for cardiac conditions, will influence the choice of chemoprophylactic agent in their particular case.

Of concern, a recent systematic review of malaria prevention in the older traveller concluded that older travellers seem less likely to comply with bite-prevention measures (118). Given the good safety profile of such measures, every effort should be made to improve their uptake by elderly travellers.

As the UK population ages yet further, the number of individuals suffering from cognitive decline will increase. Travel health practitioners need to be aware of this possibility when conducting pre-travel malaria risk-assessments for the elderly. Much more work is needed in this area across the whole of travel medicine practice.

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