Malaria prophylaxis

Question 1

Atovaquone + proguanil [malarone] - MOA and regimen

Answer 1

Causal prophylaxis - kills liver schizonts [takes 7 days]

Regimen - stop taking 7 days after leaving area

Question 2

Atovaquone + proguanil [malarone] - SE and interactions

Answer 2

SE: D+V, HA, usually well tolerated
Advise: take with milky drink/fat
-Avoid if eGFR <30

Interactions:
-HIV + TB
-Metoclopramide

Question 3

Doxycycline - MOA and regimen

Answer 3

Suppressive prophylaxis
Regimen - 3 weeks before and 4 weeks after

Question 4

Doxycycline - SE and interactions

Answer 4

SE: photosensitivity, gastritis

Interactions:
-Metabolism increased by carbamazepine and phenytoin
-Does NOT reduce efficacy of OCP
-Possible reduced efficacy of oral typhoid vaccine

Avoid:
-Children = tooth discolouration and effect on bone metabolism

Question 5

Mefloquine - MOA and regimen

Answer 5

Suppressive prophylaxis

Regimen - 1 day before and 4 weeks after

Question 6

Mefloquine - SE and interactions

Answer 6

SE: Neuropsychiatric - insomnia, anxiety, depression

Interactions: CYP3A4 metabolism - itraconazole, warfarin, DOAC

Contraindicated - epilepsy [reduced seizure threshold, reduced efficacy AEDs]

Can be used in pregnancy and breastfeeding

Once weekly

Question 7

Primaquine - MOA + contraindications

Answer 7

Causal prophylaxis
Can affect hypnozoites [important for vivax]

CI: G6PD

Question 8

Malaria prophylaxis - renal disease

Answer 8

Can use in severe renal disease = mefloquine and doxycycline

Avoid malarone eGFR <30