Antiparasitics

Question 1

Name the 6 malaria drugs

Answer 1

Cholorquine
Mefloquine
Quinine
Primaquine
Atovaquone
Proguanil

Question 2

What is the MOA of chloroquine?

Answer 2

Kills blood schizont by targeting parasite lysosome. Prevents conversion of heme to hemozin.
Heme accumulation is toxic to parasite

Question 3

How does a parasite develop resistance to chloroquine?

Answer 3

Develops membrane to pump/flush drug out so it can’t reach lysosome

Question 4

What decreases absorption of chloroquine?

Answer 4

Antacids

Question 5

Which malaria drug can not target the erythrocitic forms?

Answer 5

Primaquine

Question 6

When is mefloquine used?

Answer 6

When a community is resistant to chloroquine

Question 7

Which malaria drug can cause cardiac arrest and neuropsychiatric reactions?

Answer 7

Mefloquine

Question 8

How does the MOA of quinine differ from Chloroquine?

Answer 8

Kills blood schizont by binding to DNA, blocking replication/multiplication

Question 9

Which three malaria drugs target the lysosome/parasite food vacuole?

Answer 9

Chloroquine
Mefloquine
Primaquine

Question 10

Which two malaria drugs can target the hepatic form of malaria? Which can completely eradicate the hepatic form? Which is slower acting and can partially target the hepatic form and completely eradicate the erythrocytic form?

Answer 10

Primaquine - kill hepatic well

Proguanil - partially target hepatic, kill blood schizont well

Question 11

Which is the only malaria drug safe during pregnancy?

Answer 11

Proguanil

Question 12

Which malaria drug can target both tissue and blood schizonts? When is it used?

Answer 12

Atovaquone

Use when resistant to chloroquine

Question 13

What is the MOA of Atovaquone?

Answer 13

inhibits replication by targeting parasite Cytochrome P450, inhibiting mitochondrial ETC

Question 14

Which malaria drug should not be used prophylactically?

Answer 14

Quinine

Question 15

Which two malaria drugs are typically used in combination with eachother? Which stage(s) do each target?

Answer 15

Atovanquone - tissue and blood

Proguanil - hepatic

Question 16

What is the only parasitic drug that is a prodrug? What is its MOA?

Answer 16

Metranidazole

Obligate anaerobe ferredoxin reduces drug into reactive metabolite, binding to DNA, damaging it

Question 17

Which three organisms are targeted by metranidazole?

Answer 17

Entamoeba hystilitica
Trichomonas
Girardi Lambia

Question 18

What are the two AE of metranidazole?

Answer 18

Psycosis

Disulfiram-like reaction, blocking conversion of acetaldehyde to acetate, causing terrible hangover

Question 19

Which malaria drug should only be used for severe infections, including cerebral malaria?

Answer 19

Quinine

Question 20

What is the MOA of quinine?

Answer 20

Attached to double-stranded DNA and prevents separation, blocking multiplication

Question 21

Which malaria drug can cause GI distress and leukopenia?

Answer 21

Primaquine

Question 22

What is the MOA of Proguanil?

Answer 22

Inhibits dihydrofolate-reductase-thymidylase synthase, inhibiting DNA

Question 23

How is metronidazole eliminated through the body?

Answer 23

Eliminated in dark red/brown urine

Question 24

Which trimeseter of pregnancy should metronidazole note be used in? What other drug is it contraindicated/a dose adjustment is needed in?

Answer 24

1st

Warfarin

Question 25

Which two malaria drugs can cross the BBB? Which is used to treat cerebral malaria? Which parasitic drug can cross the BBB?

Answer 25

Mefloquine and Quinine Quinine Metronidazole

Question 26

What can dilozanide furonate, iodoquinol, and paromomycin be used to treat? (broad)

Answer 26

Luminal amoebas (they are luminal amebicides)

Question 27

Besides erythrocytic malaria, what can chloroquine also be used to treat?

Answer 27

Tissue amoebic infections

Question 28

Which two broad parasitic categories can metronidazole and tinidazole emetines be used to treat? For amoebic abscesses, what needs to be added to the treatment regimen for these drugs?

Answer 28

Luminal and tissue amoebas | One luminal agent

Question 29

What can suramin and pentamidine be used to treat? What does suramin target in the parasite?

Answer 29

Trypanosoma brucei

Question 30

What drug can be used to treat advanced stages of trypanosoma brucei? What can it enter?

Answer 30

Melarsoprol | CNS

Question 31

What can pyrimethamine + sulfonamides be used to treat? What can it pass through to treat the fetus?

Answer 31

Taxoplasma gondii | Placenta

Question 32

What is a common AE to anti-helminth drugs? What are the symptoms?

Answer 32

Mazzotti reaction Fever/chills/respiratory distress/hypotension When parasite released, leads to sepsis like syndrome

Question 33

What group of helminths does sole Praziquantel target well?

Answer 33

Trematodes

Question 34

What group of heminths are treated with albendazole and praziquantel/niclosamide?

Answer 34

Cestodes

Question 35

What group of helminths can mebendazole or pyrantel pamoate be used to treat? What is the exception?

Answer 35

Nematodes | Exception is filariasis

Question 36

Which two drugs can treat elephantiasis from wucheria bancrofti?

Answer 36

Diethylcarbamazine or Ivermectin

Question 37

What is the MOA of praziquantel?

Answer 37

Increased tegmental permeability for Ca2+ ions, causing paralysis and death

Question 38

What cestode characteristic is niclosamide not effective against? What is its MOA?

Answer 38

Cysts | Targets mitochondrial transport syndrome

Question 39

What drug is very effective against eggs, larva, and adult forms of nematodes and cestodes, including cysts?

Answer 39

Albendazole

Question 40

What is an autoimmune AE of albendazole? What other recent AE has been seen in children?

Answer 40

Alopecia | Hepatotoxicity

Question 41

What drug has more AE and is only used in severe infections instead of albendazole?

Answer 41

Thiabendazole

Question 42

What drug is poorly absorbed by the host, and is therefore good for localized helminthic infections?

Answer 42

Mebendazole

Question 43

Which two groups is mabendazole the primary drug for? What can it also treat?

Answer 43

Pin worm and round worm | Larval nematodes

Question 44

What are two MOA of mabendazole?

Answer 44

Selectively inhibits parasitic microtubules | Inhibits glucose uptake (resulting in starvation)

Question 45

Which drug selectivly binds to a parasite's nicotinic receptors, leading to parasite paralysis?

Answer 45

Pyrantel pamoate

Question 46

What is Pyrantel Pamoate contraindicated for?

Answer 46

Hepatic dysfuction

Question 47

What is an alternate drug for round work infections? What is its MOA?

Answer 47

Piperazine | Selectively inds parasite GABA receptros, inducing paralysis

Question 48

Which drug is reported to cross the BBB and can interfere with the human GABA system?

Answer 48

Piperazine

Question 49

What is diethylcarbamazine the drug of choice to treat? What reaction does this classically show?

Answer 49

``` Fliarial worms (eye worm disease) Mazzotti reaction ```

Question 50

What is ivermectin the drug of choice to treat? What are the two MOA? Can it affect human GABA? Why or why not?

Answer 50

Oncocerciasis (some form of filariasis) Binds to glutamate gated chloride channels in nerve and muscles Intensifies GABA mediated neurotranmission in nematodes No, cannot affect human GABA because it cannot cross the BBB

Question 51

What can be used to treat head lice?

Answer 51

Ivermectin