Antiparasitic

Question 1

How many species of Plasmodium (malaria parasites) infect humans?

Answer 1

5

Question 2

What are the the species of Plasmodium that infect humans?

Answer 2

Falciparum
Vivax
Ovale
Malariae
Knowlesi

Question 3

What is the most common form of malaria?

Answer 3

Falciparum malaria

Question 4

What is the most severe form of malaria?

Answer 4

falciparum malaria

Question 5

What form of malaria is often lethal?

Answer 5

Cerebral form

Question 6

Vivax malaria is…?

Answer 6

a milder but common form of malaria

Question 7

Which form of malaria can relapse due to dormant hypnozoites that remain in the liver and are NOT affected by blood-stage antimalarials?

Answer 7

Vivax malaria

Question 8

What are the two types of antimalarial chemotherapy?

Answer 8

Prophylaxis
Treatment of active or latent infection

Question 9

What antimalarial agents are used for prophylaxis?

Answer 9

Cholorquine
Primaquine

Question 10

What antimalarial agents are used to treat active or latent infections?

Answer 10

Chloroquine
Primaquine
Artemether/lumefantrine

Question 11

What is another term for antimalarials?

Answer 11

Schizonticides

Question 12

What are the two stages of malaria that drugs target?

Answer 12

Liver stage
Blood stage

Question 13

During what stage of malaria do patients experience symptoms?

Answer 13

Blood Stage

Question 14

Malaria drugs that target the blood stage produce a ____ cure

Answer 14

Clinical

Question 15

Malaria drugs that target the liver stage produce a ____ cure

Answer 15

radical
(of relapsing malaria)

Question 16

Are blood stage antimalarial effective against liver stage parasites?

Answer 16

No

Question 17

What antimalarial drugs disrupts disease transmission? And by what activity?

Answer 17

Artemether and Primaquine
gametocidial activity

Question 18

Chloroquine and Artemisinins are antimalarial drugs that target the ____ stage of malaria

Answer 18

Blood stage

Question 19

Primaquine is an antimalarial drug that target the ____ stage of malaria

Answer 19

Liver stage

Question 20

Orally effective, long half-lives and low toxicity are properties of what type of antimalarial agent?

Answer 20

Prophylactic

Question 21

What does chemoprophylaxis treatment for malaria prevent?

Answer 21

symptomatic blood stage

Question 22

How is antimalarial drug for a US traveler selected?

Answer 22

dependent on the resistant pattern of the intended destination

Question 23

Since no regimen is fully protective for malaria, what else is important?

Answer 23

prevention of mosquito bites

Question 24

Chloroquine is a weak organic acid/base?

Answer 24

base

Question 25

inhibition of biocrystalization is the MOA of what antimalarial drug?

Answer 25

Chloroquine

Question 26

what are the therapeutic uses of chloroquine?

Answer 26

clinical cure and prophylaxis against sensitive strains

Question 27

what is used for prophylaxis and treatment of malaria during pregnancy

Answer 27

chloroquine

Question 28

chloroquine is effective/ineffective against most strains of P. falciparum in Africa, Asia and s. America?

Answer 28

ineffective

Question 29

Adverse reactions of chloroquine depend on ...

Answer 29

low-dose (prophylaxis) vs. high-dose (clinical cure)

Question 30

Cholorquine targets the blood/liver stage of malaria?

Answer 30

blood

Question 31

True or False: chloroquine is generally well-tolerated at lower doses?

Answer 31

true

Question 32

At higher-doses, adverse reactions of chloroquine include:

Answer 32

pruritus headache GI CV toxicity

Question 33

Artemether route of administration is...

Answer 33

oral

Question 34

artemether is derived from ...

Answer 34

medicinal Chinese plant quinghao

Question 35

the MOA of artemether is

Answer 35

unclear (drugs may form toxic free radicals in the presence of heme)

Question 36

what property of artemether makes the drug NOT useful for prophylaxis?

Answer 36

short half-life

Question 37

what is artemether used with in a fixed-dose combination

Answer 37

lumefantrine

Question 38

what is important about lumefantrine?

Answer 38

it is long acting, half life of 4.5 days, it sustains antimalarial activity during the frequent sub-therapeutic trough levels or artemether

Question 39

what is an important therapeutic use of artemether-lumefantrine?

Answer 39

first line oral of MDR falciparum malaria

Question 40

inactive counterfeits that closely mimic genuine drugs for malaria are common/uncommon

Answer 40

common

Question 41

artemether adverse reactions are

Answer 41

not well characterized, generally safe

Question 42

adverse reactions of artemether (in animal studies) include

Answer 42

neurotoxicity (in animals) and potent embryo toxicity (in animals)

Question 43

artemether is used to treat ____ stage of malaria

Answer 43

blood stage

Question 44

Why is it important that chloroquine is a weak organic base?

Answer 44

it becomes ionized in acidic environment which allows ion trapping in parasite food vacule (an infected RBC)

Question 45

what is the food source for malaria parasites?

Answer 45

globin from hemoglobin

Question 46

hematin is ____ to malaria parasites

Answer 46

toxic

Question 47

what is biocrystallization and why is it important for malaria parasites?

Answer 47

malaria parasites: hematin ---(biocrystallization) ---> non-toxic hemozoin

Question 48

resistance to chloroquine is due to ....

Answer 48

mutated efflux transporter (PfCRT) that prevents drug accumulation

Question 49

Primaquine targets ____ stage of malaria

Answer 49

liver stage

Question 50

what is the MOA of primaquine?

Answer 50

it is unknown

Question 51

what are the three therapeutic uses of primaquine (oral)?

Answer 51

1. with chloroquine to achieve clinical and radical cure of vivax/ovale malaria 2. for terminal prophylaxis AFTER completion of travel to vivax/ovale endemic areas 3. for primary prophylaxis against all species if other agents are inappropriate

Question 52

what are the two types of prophylaxis that are uses of primaquine?

Answer 52

primary and terminal

Question 53

primaquine is well tolerated but causes hemolytic anemia in _____ deficient patients

Answer 53

G6PD

Question 54

Besides G6PD-deficient patients, primaquine is contraindicated for

Answer 54

pregnant females (fetal G6PD status cannot be determined)

Question 55

What is a common genital STI protozoal infection in the US?

Answer 55

trichomoniasis

Question 56

giardiasis, amebiasis and cryptosporidiosis are ...

Answer 56

all GI protozoal infections that are common in the US

Question 57

amebiasis infection occurs mainly in the GI and the infection can ....

Answer 57

be asymptomatic, mild-mod (colitis) or severe (dysentery)

Question 58

antiprotozoal agents for GI protozoal infections are classified as ____ or ______

Answer 58

systemic or GI luminal

Question 59

what is a systemic antiprotozoal agent?

Answer 59

metronidazole

Question 60

what is a luminal antiprotozoal agent?

Answer 60

paromomycin

Question 61

metronidazole MOA

Answer 61

prodrug converted to DNA-damaging metabolite in anaerobic organisms

Question 62

two therapeutic uses of metronidazole are ...

Answer 62

1. treat amebiasis (given in combo with a luminal amebicide to eradicate luminal survivors) 2. anaerobic bacterial infections

Question 63

why is metronidazole given in combination with a luminal amebicide?

Answer 63

to eradicate luminal survivors because metronidazole levels in the GI tract are low due to its complete oral absorption

Question 64

what class is parmomycin?

Answer 64

aminoglycoside

Question 65

MOA of paromomycin

Answer 65

binds to 30S subunit to inhibit protein synthesis

Question 66

is paromymycin absorbed from the GI tract?

Answer 66

No, it is a luminal antiprotozoal agent

Question 67

what is the prototype drug for benzimidazoles?

Answer 67

albendazole

Question 68

MOA of albendazole

Answer 68

inhibits polymerization of parasite B-tubulin, preventing formation of cytosolic microtubules

Question 69

Antihelminthics include ...

Answer 69

albendazole, ivermectin

Question 70

uses for albendazole and how is it used?

Answer 70

1. enterobiasis infection, single 400 mg dose repeated 2 weeks later 2. cestode and roundworm infections

Question 71

adverse effects of albendazole

Answer 71

teratogenic effect in animal, long term--liver toxicity, bone marrow suppression

Question 72

immobilization by tonic muscle paralysis is the MOA of what antihelminthic drug?

Answer 72

Ivermectin

Question 73

how does ivermectin cause tonic muscle paralysis in helmniths?

Answer 73

(+) glutamate-gated Cl- channels only found in invertebrate neurons, causes hyperpolarization of neuronal membrane

Question 74

how is ivermectin kept out of the CNS in the host?

Answer 74

P-glycoprotein efflux transporter in host BBB

Question 75

three uses of ivermectin include:

Answer 75

1. broad spectrum agent to treat ticks, fleas, mites in vet medicine 2. onchocerciasis (river blindness) 3. scabies, head lice

Question 76

adverse effects of ivermectin

Answer 76

mazzotti reaction teratogenic potential (cleft palate in animals)

Question 77

what is a mazzotti reaction and when does it occur?

Answer 77

adverse reaction of ivermectin that occurs in onchocerciasis. It is an immune reaction to drying worms. Includes: pruritus, rash, fever, lymphedema