Antiparasitics Flashcards Preview

Block 3 Pharm > Antiparasitics > Flashcards

Flashcards in Antiparasitics Deck (72)
1

Random US parasites

Helminth infections in over 1 million
Toxocara (roundworms) from dogs and cas are 14%pop
malaria~2000 year
trichonomas vag~ 3 million
Giardia: 10% population

2

Infection of parasites associated with

poor economic conditions
encysted tapes in 25% inner city children and leading cause of seizures in kinds in hispanice

3

Cure vs control

have to eradicate several staes of parasite in host
-enZ unique to host and indespendible only to parasite

4

Nematode (roundworm) cycle

see eggs in feces--> then will hatch into a filiraform to pentrate skin and hang in our small intestine

5

Damages microtulbes
inhibits glycogen uptake
can't move or get E... DEATH you nasty roundworm!

Mebendazole
(mictrotubule destruction... now they can get glycogen and they can't move!)

6

effective for many intestinal roundworms and kills some ova... damages microtubules

Mebendazole

7

Use of Mebendazole

kills intestinal roundworms and some ova

8

Absorption of Mebendazole

low systemic bioavailability = low systemic toxicity

9

Albendazole uses

Echinococcus or cuteanous larval migrans and neurocystocerosis d/t Taenia solium

10

Used for echinoccosus or cutaneous larval migrans or neurocysticercosis due to Taenia solium

Albendazole
EICK.. they're all bendy under my skin and in my BRAIN!

11

same as mebendazole, liver -->albendazole sulfoxide (active)
good systemic distribution

Albendaozle
(EICK.. they're all bendy uder my skin and in my BRAIN!)

12

How is albendazole differenet from mebendazole

converted quickly be liver to active form for better distribution which is why is

13

Mech of Albendazole in depth

fuck with microtubules
inhibits glucose uptake
can't get food or move = die

14

What is special about albendazole metabolite

more activated by liver and great distribution

15

Side effects of Albendazole

duh.. elevates hepatic enZ bc converted in liver... and makes tummy hurt

16

affects energy metabolism via inhibition of mitochondrial fumarate reductase in HOOKWORMS

Thiabendazole
(tHiabendazole has an H... hookworms)

17

MEch of Thiabendazole for HOOKWORMS
(I'd be FUMING if i had hookworms)

affects E metabolism
inhibiting mitochondiral fumarate reductase in hookworms
(I'ld be FUMING if i had hookworms)

18

Mech of Thiabendazole for Strongyloidesl

inhibits assembly of parasitic microtubules.

19

Thiabendazole uses:

Strongyoids
cuteanous larva migrans from dog or cat hookworms

20

Strongyloides
cuteanous larva migrans from dog or cat hookworms

Thiabendazole

21

absorption of Thiabendazole

oral form rapidly absorbed

22

side effects of thiabendazole

nauseua, vomit, dizzy

23

Pyrantel Pamoate mechanism

depolarizing neuromuscular blocker, causing spastic paralysis of worm
Pyrantel Pamoate causes dePPPPPolarization and PPPPParalysis

24

uses of Pyrantel Pamoate

hookworm, pinworm, roundworm

25

increase Ca++ permeability.. causes muslce cnx... spastic paralysis

Praziquantel causes PPPPPPermeability

26

Mech of Praziquantel

increase Ca++ permeability.. causes muslce cnx... spastic paralysis
(PPPPPraziquantel... increase PPPPermeability)

27

drug of choice for Schisotosoma

Praziquantel
I pray this Schits over soon"

28

Use of Praziquantel

Schistosomiasis (also for taneia solium to prevent neurocysteriocorcosis)

29

Tape worm drugs

Praziquantel, Albendazole, Paromomycin sulfate

30

good activity for schistosomiasis but also for tania solium bc kills eggs to you can avoid cysticercosis

Praziquantel

31

Used to treat neurocysticercosis

Albendazole (be careful in poeople with seizures)

32

Used as 3rd choice for those that don't tolerate Praziquantel or Albendazole for tapeworms

Paromomycin sulfate
"MOM.. i have tape worms"

33

Key with anti-malarials

don't prevent infection.. they only prevent progression to symptomatic malaira

34

____ in mosquito salivary gland are injected into human blood

Sporozoites

35

Exoerythrocytic stage—

sporozoites multiply in liver to form tissue schizonts

36

Escape from liver into bloodstream as_____, which begins the erythrocytic stage; the merozoites invade red blood cells and multiply in them to form

merozoites
blood schizonts

37

Infected erythrocytes eventually rupture releasing a new crop of ______ this erythrocytic cycle may be repeated several times

merozoites;

38

What form are we always going to target with anti-malarial drugs

always the blood schizonts

39

• have only one cycle of liver cell invasion and multiplication (liver infection ceases
spontaneously in

P. falciparum and P. malariae

40

have dormant hepatic stage (hypnozoite) that can cause relapses
• treatment requires elimination from both the liver and blood

P. vivax and P. ovale •
Liver has 5 letters and so do these malaria

41

Blood schizonticide:
parazitized erythrocytes concentrate the drug 25 fold by pH dependent mechanism into acidic vacuoles

Chloroquine
(think chloride because its negatve and will go to low pH

42

which trophozoites are suspeptible to Chloroquine (quine sounds like 4... all are suspetible and stops heme quads!)

ones actvely degrading hemaglobin... the chloroquine inhibits heme polymerization and the heme accumulate to toxic levels === death!

43

Use of Chloroquine

all 4 species
will eradiate P. malariae and P. falciparum but wont cure P. vivax and ovale (still have liver form)

44

Tx all 4 species
will eradiate P. malariae and P. falciparum but wont cure P. vivax and ovale (still have liver form)

Chloroquine
(careful for P.falciparum resistance)

45

Side effect of chloroquine

visual impairment
(chloroquine... 4 eyes!!!! b'c quine sounds like quad... also for all four... alsp think stops heme from going to 4)

46

Mech of Mefloquine

sim to chloroquine

47

use to tx chloroquine resistant P.falciparum and P.vivax and as prophylaxsis in chloroquine resistant areas

Mefloquine

48

What pts should not recieve mefloquine

pts with eplilepsy or pychiatric disorders

49

Black box warning for Mefloquine

psychiatric effects like anxiety, paranoa and depression as well as vestibular effects
"Me-floquine will make ME crazy!"

50

◊ ubiquinone analog
inhibits malarial mitochondrial election transport ~ cyt bc1
fucks up pyrimdine synthesis

atovaquone

51

prodrug activated by hepatic CYP2C9 to inhibi malarial dihydrofolate reductase to block folate synthesis--- pyrimidine synthesis

Proguanil
"pro as in prodrug"

52

These two will inhibit protozoal pyrimidine synthesis

Atovaquone
Proguanil

53

Mech of Atovaquone
(think ABC's~~~ goes A for atovaquone and BC for cyctochorm BC1)

ubiquinone analog
inhibits malarial mitochondrial ETC by disrupting Cyt BC1
Fucks up their pyrimidine sythesis

54

Mech of Proguanil

prodrug activated by hepatic CYP2C9
inhibits malarial dihydrofolate reductase block folate synthesis--- pyrimidine synthesis

55

Why do we use Proguanil and atovaquone together for chloroquine resistant P.falciparum

because synergistic effect on mitochondria when given together and fewer side effects

56

Mech of quinine

similar to chloroquine
RBC infected with parasites...inside acidic vacuoles which concentrates the drug. The drug prevents the hemes that the trophazoites are degrading from polymerizing into a toxic free heme... build up toxic heme = death

57

Uses of Quinine

Schizonticide for all four
alternative for P.Falciparum resistant to Chloroquine

58

similar to chloroquine
RBC infected with parasites...inside acidic vacuoles which concentrates the drug. The drug prevents the hemes that the trophazoites are degrading from polymerizing into a toxic free heme... build up toxic heme = death

Quinine and Mefloquine
Diff side effects

59

Both Quinine and Mefloquine are alt for Chloroquine reistant P. Falciparum, whats the differece

Mefloquine: black box on pyschiatric issues and epilepsy
Quinine: Cinchonism, cardiate effects simular to qunidine or nausea

60

Side effects of quinine

cinchonism: headache, visual disturbance, dizziness, tinnitus
GI
cardiac effects similar to quinidine

61

cinchonism: headache, visual disturbance, dizziness, tinnitus
gastric irritation, nausea, vomiting
cardiac effects similar to quinidine

sides for quinine

62

Doxycycline mech

depress dihydroorotate
dehydrogenase activity,
can't make pyrimidines

63

fucks with dihydroorotate DH activity
then the malaria can't make pyrimides

Mech of Doxycycline
"Doxy got all those D's
Dihidroorotase DH"

64

effective for multidrug-resistant P. falciparum, especially in combination with quinine
• also for malarial prophylaxis

Doxyclycine

65

Drug to kill liver hypnoschizots

Primaquine

66

Mechanism of Primaquine

act as oxidants will kill liver hypnozoites

67

radical cure or terminal prophylaxis of P. vivax and P. ovale because it will kill dormant liver schizonts; usually given at end of therapy with chloroquine; for travelers to malarious regions, primaquine is usually given after return home

Primaquine

68

radical cure for P. vivax and P. ovale and used with drugs to kill blood schizonts

Primaquine

69

Drug can also be used to tx Pneumocystisi jiroveci pneumonia in AIDS pts

Primaquine

70

uses of Primaquine

liver schizonts: P. vivax and P. ovale and pneumocystis jirovveci

71

Side effects of primaquine

hemolytic rxns in those with G6P DH deficiency

72

see hemolytic rnx in those with GP6 deficiency

Primaquine