MALARIA

Question 1

Bite protection

Answer 1

• Mosquito nets impregnated with permethrin

• Diethyltoluamide (DEET) 20-50% (50% lasts longer protection)

Question 2

DEET

Answer 2

o Suitable for anyone over 2 months old

o Avoid ingestion - was hands before eating

o Suitable for pregnancy and breastfeeding (wash breast before feeding)

o Apply DEET after sunscreen
 DEET reduces SPF of sunscreen - use high SPF lotion

Question 3

DEET and pregnancy

Answer 3

Suitable for pregnancy and breastfeeding (wash breast before feeding)


Question 4

DEET and sunscreen

Answer 4

DEET reduces SPF of sunscreen - use high SPF lotion

DEET after sunscreen

Question 5

Prophylaxis treatment

Answer 5

Malarone
Chloroquine
Proguanil
Mefloquine
Doxycycline

Question 6

Malarone

Answer 6

1-2 days before travel
1 daily
1 week after travel
Max use: 1 year

Question 7

Chloroquine

Answer 7

1 week before travel
1 weekly
4 weeks after travel
long term

Question 8

proguanil

Answer 8

1 week before travel
1 daily
4 weeks after travel
long term

Question 9

mefloquine

Answer 9

2-3 weeks before travel
1 weekly
4 weeks after travel
Max use: 1 year

Question 10

Doxycycline

Answer 10

1-2 days before travel
1 daily
4 weeks after travel
max use: 2 yrs

Question 11

prophylaxis should be continued for 4 weeks after leaving the area, except for the following which should be stopped one week after leaving

Answer 11

atovaquone with proguanil hydrochloride

Question 12

Illness occurring within 1 year, especially 3 months of return

Answer 12

might still be malaria – see doctor early, mentioning malaria

Question 13

Proguanil in pregnancy

Answer 13

can no longer be used in malaria prophylaxis in pregnant patients. Only chloroquine now licenced

Question 14

Pregnancy

Answer 14

• Avoid traveling to malarious regions
• Chloroquine can be given - avoid other medications


Question 15

Folic acid and antimalarials

Answer 15

give folic acid (dosed as a pregnancy at high risk of neural tube defects) for the length of time that it is used during pregnancy
5mg OD

Question 16

if a pregnant woman is travelling to high risk areas or there is resistance to other drugs, consider this drug in the 2nd and 3rd trimesters. it can be used in 1st trimester with caution if benefits outweigh risks.

Answer 16

mefloquine

Question 17

use of doxycycline for prophylaxis during pregnancy

Answer 17

doxy is CI in pregnancy
however it can be used for malaria prophylaxis if other regimens are unsuitable, and if the entire course of doxy can be completed before 15 weeks gestation

Question 18

doxycycline is contraindicated in pregnancy however it can be used for malaria prophylaxis if other regimens are unsuitable, and if the entire course can be completed before ….

Answer 18

before 15 weeks gestation

Question 19

this combination should be avoided during pregnancy however it can be used during 2nd and 3rd trimester if no suitable alternative. you will also need to give folate supplementation during the length of time it is used during pregnancy (using 5mg which is the dose for pregnancy at high risk of neural tube defects)

Answer 19

Atovaquone with proguanil hydrochloride

Question 20

Asplenia

Answer 20

Asplenic patients are at risk of severe malaria

Question 21

Epilepsy

Answer 21

Avoid chloroquine and mefloquine – reduces seizure threshold

Question 22

doxycycline can be used for malaria prophylaxis in pt with history of epilepsy. however, it interacts with some anti epileptics and its dose may need adjustment. name and explain some interactions

Answer 22

inducers:carbamazepine, phenytoin, barbiturates

these drugs DECREASE the concentration of doxycycline. adjust dose of doxy

Question 23

Warfarin

Answer 23

• Begin treatment 2-3 weeks before departure
• INR should be stable before departure
• Measure INR before antimalarials, 7 days after starting and after completing course
• Prolonged stay – check INR regularly

Question 24

travellers taking warfarin need to begin malaria chemoprophylaxis ….. before departure and their INR needs to be stable before departure

Answer 24

2-3 week before departure

Question 25

when should warfarin INR be measured for pt taking chemoprophylaxis?

Answer 25

before starting chemoprophylaxis 7 days after starting after completing course

Question 26

Mefloquine caution

Answer 26

* History of psychiatric disorders - if these develop = STOP and seek medical * attention * History of convulsions * Reduces seizure threshold

Question 27

Chloroquine side effects

Answer 27

* History of convulsions * Can be retinotoxic – eye symptoms - ototoxicity

Question 28

Proguanil cautions

Answer 28

* Renal Impairment - reduce dose

Question 29

in order to use standby emergency treatment appropriately, the traveller should be provided with

Answer 29

Travellers should be provided with written instructions: Seek urgent medical attention if fever (38°C +) develops 7+ days after arriving in a malarious area

Question 30

should you use the same drug that was used for chemoprophylaxis for emergency standby treatment

Answer 30

A drug used for chemoprophylaxis should not be considered for standby treatment for the same traveller due to concerns over drug resistance and to minimise drug toxicity.

Question 31

A patient wants some malaria tablets before he goes away next week. you look at his PMR and see that he is taking takes azithromycin for lyme disease (500mg OD for 17 days). from this information which anti-malarial would you ideally want to avoid and why?

Answer 31

ideally avoid chloroquine because A + C = increased risk of CV events including angina, chest pain and HF and mortality.

Question 32

chloroquine is associated with ocular toxicity. this is unlikely if the dose of chloroquine phosphate does not exceed ….

Answer 32

4mg/kg daily

Question 33

chloroquine is …toxic so there is increased risk of …toxicity with drugs e.g.

Answer 33

ototoxic ototoxicity risk with loop diuretics, aminoglycosides, vincristine vinblastine etc

Question 34

important side effect of mefloquine and which patients it is contraindicated in

Answer 34

potentially serious neuropsychiatric reactions common: abnormal dreams, insomnia, anxiety, depression psychiatric symptoms should be regarded as potentially prodromal for a more serious event adverse reactions may occur and persist up to several months after discontinuation due to Long half life avoid for prophylaxis if Hx psychiatric disorders (including depression) or convulsions

Question 35

a patient needs some anti malarial tabs for prophylaxis. she takes sertraline 100mg daily. she is contraindicated for this drug because…

Answer 35

mefloquine contraindicated for prophylaxis if Hx psychotic disorders including depression it is associated with potentially serious neuropsychiatric reactions long half life so can persist up to several months after discontinuation

Question 36

mefloquine - family of quinine so it has this important interaction with drugs

Answer 36

increased risk of QT prolongation with amiodarone, antipsychotics, dronedarone, fluconazole, erythromycin, methadone, etc

Question 37

a patient is taking atovaquone with proguanil for prophylaxis of malaria. they develop diarrhoea and vomitting. what does this mean.

Answer 37

caution in diarrhoea or vomiting as reduced absorption