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Flashcards in Anti-Malarials Deck (60):
1

Drugs for the prevention of malaria in travelers in areas without resistant P. falciparum

Chloroquine

2

Drugs for the prevention of malaria in travelers in areas with chloroquine resistant P. falciparum

Atovaquone + Proguanil (Malarone) Mefloquine

3

Drugs for the prevention of malaria in travelers in areas with multidrug resistant P. falciparum

Doxycycline

4

Terminal prophylaxis of P. vivid and P. ovale infections; alternative for primary prevention

Primaquine

5

4 species of plasmodium which cause malaria

– Plasmodium falciparum – Plasmodium vivax – Plasmodium malariae – Plasmodium ovale

6

Most virulent species of plasmodium; responsible for most of serious complications & deaths

Plasmodium falciparum

7

Drug resistance (important therapeutic problem is most notable with this virulent species)

Plasmodium falciparum

8

primarily pathogenic to monkeys; now known to cause illness to humans in Asia

P. knowlesi

9

Stage 1 of lifecycle: Transmission of (1) by Plasmodium-infected Anopheles into the bloodstream

1. sporozoites

10

Stages 2&3 of lifecycle: (1) invade (2); divide forming (3)

1. Sporozoites 2. Liver 3. multinucleated schizonts (pre-erythrocytic stage)

11

Active against hepatic-stage schizonts (stages 2 and 3)

Atovaquone-proguanil and primaquine

12

Stage 4: (1) rupture & release (2) to blood; invade RBC, forming (3) & later (4)

1. Schizonts 2. merozoites 3. trophozoites 4. multinucleated schizonts (erythrocytic stage)

13

Blood-stage schizonticides (stage 4)

Quinoline derivatives (Chloroquine, amodiaquine, quinine, quinidine, mefloquine, primaquine, lumefantrine & halofantrine) Antifolates (sulfadoxine-pyrimethamine, atovaquone-proguanil) Antimicrobials (tetracycline, doxycycline and clindamycin) Artemisinin derivatives interrupt schizogony within red cells

14

Quinoline derivatives (Chloroquine, amodiaquine, quinine, quinidine, mefloquine, primaquine, lumefantrine & halofantrine)

stages 2, 3, 4, 5 Active against hepatic-stage schizonts Active against blood-stage schizonticides gametocidal drug (primaquine)

15

Antifolates (sulfadoxine-pyrimethamine, atovaquone-proguanil)

stages 2, 3, 4 Active against hepatic-stage schizonts Active against blood-stage schizonticides

16

Antimicrobials (doxycycline)

Active against Blood-stage schizonticides (stage 4)

17

Artemisinin derivatives interrupt schizogony within red cells

Active against Blood-stage schizonticides (stage 4) gametocidal drugs (Stage 5)

18

Stage 5. Some merozoites differentiate into ♂ or ♀ (1); ingested by the Anopheles mosquito & mature in the mid-gut to (2) (migrate to the salivary glands of the mosquito)

1. gametocytes 2. sporozoites

19

gametocidal drugs

Artemisinin derivatives and Primaquine

20

Tissue schizonticides

drugs that eliminate developing or dormant liver forms

21

Blood schizonticides

drugs that act on erythrocytic forms of the parasites

22

Gametocidal drugs

drugs that kill sexual stages & prevent transmission to mosquitoes

23

Causal prophylactic drugs

prevent erythrocytic infection

24

Treatment & chemoprophylaxis of infection with sensitive parasites

Chloroquine

25

Treatment of severe P. falciparum infections, especially cerebral malaria

Quinine

26

Chemoprophylaxis and Treatment of infections with P. falciparum

Mefloquine

27

Treatment of infections with some chloroquine‐resistant P. falciparum; could be combined with artesunate; preventive therapy in endemic areas

Sulfadoxine-pyrimethamine

28

Treatment and chemoprophylaxis of P. falciparum infections

Atovaquone + Proguanil (Malarone)

29

Radical cure and terminal prophylaxis of infections with P. vivax and P. ovale; alternative chemoprophylaxis for all species

Primaquine

30

Drug of choice for treatment of P. falciparum-sensitive malaria & chemoprophylaxis of malaria

Chloroquine

31

Mutations in a (1) correlates with P. falciparum resistance

1. putative transporter (PfCRT)

32

Terminate fever in 24-48 hours; Clears parasitemia in 48-72 hours

Chloroquine

33

Almost complete GIT absorption

Chloroquine

34

mechanism of action: concentrates in parasite food vacuoles; increases (1) and toxicity to parasite

1. free heme Chloroquine; Amodiaquine

35

Amodiaquine a/e

Agranulocytosis, aplastic anemia and hepatotoxicity are common adverse effects

36

Chloroquine a/e

Pruritus Nausea, abdominal pain, blurring of vision Hemolysis in persons deficient in G6PD Hypotension ECG changes: QRS widening; T wave abnormalities

37

First line therapies for P. falciparum malaria, especially cerebral malaria

Quinine

38

Alkaloid from bark of cinchona tree

Quinine

39

Rapid-acting, highly effective schizonticide against all four human malaria parasites

Quinine

40

Quinine: gametocidal against (1) but not (2)

1. P. vivax and P. ovale 2. P. falciparum

41

Quinine versus quinidine - which has shorter half life

Quinidine

42

Quinine a/e

Cinchonism: Tinnitus; Headache; Visual disturbances; Nausea; Dizziness; Flushing Hypersensitivity reactions Hemolytic abnormalities Hypoglycemia ECG abnormalities

43

Contraindicated with quinine

Mefloquine Al3+ containing antacids warfarin and digoxin

44

Strong blood schizonticidal activity against P. falciparum and P. vivax

Mefloquine

45

Disrupts plasmodia mitochondria electron transport

Atovaquone + Proguanil (Malarone)

46

Acts against Tissue/Erythrocytic schizonts

Atovaquone + Proguanil (Malarone)

47

Atovaquone + Proguanil (Malarone) a/e

Abdominal pain, nausea, vomiting, diarrhea, rash

48

Contraindication Atovaquone + Proguanil (Malarone)

Co-administration with tetracycline or rifampin

49

Q image thumb

A image thumb
50

Active drug = Cycloguanil, a
triazine metabolite

Proguanil

51

Folate synthesis blockade ‐ selec􀆟􀆟ve ↓ of
plasmodial dihydrofolate reductase
activity)

Proguanil

52

Erythrocytic forms of all four human
malarial species

Pyrimethamine

Proguanil

53

↓Bacterial protein synthesis (also ↓Protein synthesis in plasmodial species)

Doxycyclin and Tetracyclin

54

a/e of doxycyclin and tetracyclin

GI symptoms; photosensitivity

55

standard prophylactic drug in SE
Asia

Doxycyclin (in combination with Mefloquine)

56

Available as a fixed dose combination with Artemether – 1st line therapy for
uncomplicated malaria in most of Africa

Lumefantrine

57

a/e of Halofantrine 

Dose-related QT and PR intervals prolongation
Embryo-toxic, thus contraindicated in pregnancy

58

production of free radicals following iron catalyzed cleavage of artemisinin endoperoxide bridge in the parasite’s food vacuole 

 

Artemisinin

59

inhibition of parasite’s calcium ATPase

Artemisinin

60

Artemisinin a/e

N/V

diarrhea, dizziness

 

Rare:

neutropenia, anemia, hemolysis, allergic reactions