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Flashcards in Antimalarials Deck (37):
1

which form of malaria have two types of stages/parasite forms to eliminate and why

-plasmodium vivax and ovale both have a dormant hepatic stage so both erythrocytic and hepatic parasites must be eliminated

-plasmodium falciparum and malariae only have erythrocytic parasites to eliminate

2

which form of malaria can have an incubation period that can last years

plasmodium malariae

3

symptoms of malaria

malaria paroxysm (sudden attack) - fever, anemia, splenomegaly, jaundice, hepatomegaly

4

which form of malaria is most severe and why

plasmodium falciparum --> cerebral malaria
-irritability, seizure, coma
-also respiratory distress syndrome, diarrhea, severe thrombocytopenia, spontaneous abortion, hypoglycemia

5

treatment of malaria should be guided by what

-species of infecting plasmodium
-clinical status of patients
-drug susceptibility of infecting parasites

6

major antimalarial drugs

CAM PADS Q

Chloroquine
Quinine and Quinidine
Mefloquine
Primaquine
Atovaquone
Sulfadoxine-Pyrimethamine
Doxycycline
Artemisinins

7

clinical application of chloroquine

treatment and prophylaxis of plasmodium vivax and ovale

sensitive uncomplicated falciparum

8

MOA of chloroquine

prevents biocrystallization of hemoglobin breakdown product heme to non toxic hemozoin --> accumulation of heme --> lysis of parasite and RBC --> effective against blood parasites and not liver parasites

9

what is resistance against chloroquine

plasmodium falciparum -- due to mutations in putative transporter, PfCRT

10

adverse effects of chloroquine

Pruritus (most common)
Hemolysis in G6PD deficiency

11

contraindications of chloroquine

patients with psoriasis or porphyria (precipitate attacks)

retinal or visual field abnormalities

12

what are quinine and quinidine used for

severe forms of plasmodium falciparum malaria

quinine is oral and quinidine is parenteral

13

mechanism of quinine and quinidine

depresses O2 uptake and carb metabolism --> intercalates into DNA --> disrupts parasites replication and transcription --> only good for blood parasites

14

adverse effects of quinine and quinidine

CHHHUBES

Cinchonism - tinnitus, visual probs, dizziness
Hypersensitivity - skin rash, urticaria
Hematological abnormalities
Hypoglycemia - stimulates insulin release
Uterine contractions
Blackwater fever - hemolysis and hemoglobinuria
ECG abnormalities - QT prolongation
Severe hypotension - too rapid IV infusion

15

contraindications of quinine and quinidine

-visual or auditory problem (cinchonism)
-cardiac abnormalities (ECG problems)
-raises levels of warfarin and digoxin
-reduced dose in renal insufficiency
-don't use with mefloquine

16

MOA of Mefloquine and its clinical application

destruction of asexual blood forms of malarial pathogens

chemoprophylaxis in preggos in chloroquine resistant areas

17

what drug does mefloquine causes a resistant to

quinine

18

adverse effects of Mefloquine

Neurologic and psychiatric toxicities
Cardiac conduction defects

19

contraindications of Mefloquine

-Do not administer with quinine, quinidine, and halofantrine
-Patients with history of neurologic, psychiatric, and cardiac problems

20

drug of choice for dormant liver form of plasmodium vivax and ovale

primaquine

21

adverse effects of primaquine

Hemolysis
Methemoglobinemia
both especially in G6PD deficiency since primaquine further decreases available GSH by oxidizing it to GSSG

22

contraindication of primaquine

G6PD deficiency
Pregnancy - fetus is relatively G6PD deficient

23

what is Malarone

Atovaquone + Proguanil

24

MOA of malarone and clinical application (what is it again)

atovaquone + proguanil

disrupts mitochondrial electron transport --> used for plasmodium falciparum

25

contraindications of Malarone (name what it is)

Atovaquone + Proguanil

Pregnancy

26

inhibitors of folate synthesis used as antimalarials

Pyrimethamine
Proguanil
Sulfadoxine

27

MOA of the antimalarial inhibitor of folate synthesis

Pyrimethamine + Proguanil = inhibitor plasmodial dihydrofolate reductase

Sulfadoxine = inhibit dihydropteroate synthase

28

of the three antimalarial inhibitor of folate synthesis, which works weakly on hepatic forms

Proguanil

29

adverse effects of antimalarial inhibitor of folate synthesis (individually)

Pyrimathamine-Sulfadoxine: Erythema Multiforme, Stevens-Johnson, Toxic epidermal necrolysis

Proguanil: mouth ulcers, alopecia

Sulfadoxine: Hematological, GI, CNS, dermatologic, and renal toxicities

30

clinical application of doxycycline

prophylaxis for all form
treatment of p. falciparum
not used against liver stages

31

adverse effects of doxycycline and contraindications

-stunting of growth
-discoloration and hypoplasia of teeth
-fatal hepatoxicity in pregnancy


-don't use in pregnancy and children under 8

32

types of artemisinins

artesunate
artemether
dihydroartemisinin
coartem

33

MOA of artemisinins

binds to iron --> breaks down peroxide bridges --> free radical generation -> damage parasitic protein

34

other antimalarials

Clindamycin
Halofantrine
Lumefantrine

35

adverse effects of halofantrine

teratogenic

36

when is mefloquine usually given

when chloroquine resistant especially in preggos

37

what is given as prophylaxis when chloroquine resistant

mefloquine, doxycycline, primaquine

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