Pharm Antiprotozoal Drugs

Front 1

What are the antimalarial drugs?

Back 1

Chloroquine, mefloquine, primaquine, quinine, antifolates

Front 2

What are two blood schizonticides, that kill the malaria parasites in the erythrocyte?

Back 2

Chloroquine and quinine

Front 3

What is the MOA of chloroquine? SE

Back 3

Concentrates in parasite food vacuoles and prevents hemoglobin breakdown product heme to hemozoin. Heme is toxic to the parasite.

Retinal damage, color vision changes, pruritus,hemolytic anemia in G6PD deficiency, auditory impairment, and toxic psychosis.

Front 4

Chloroquine is the DOC for?

Back 4

Nonfalciparum and sensitive falciparum malaria. It is also a chemoprophylaxis for malaria.

Note: it is solely a blood schizonticide

Front 5

What is the alternative treatment for Plasomodium falciparum that are resistant against chloroquine?

Back 5

Artemether & artesunate or quinine with pyrimethamine/sulfadoxine

Front 6

MOA of quinine and its use?

Back 6

Complexes with dsDNA to prevent strand separation, resulting in block of DNA replication and transcription to RNA.

Is used for treatment of severe or complicated falciparum, and treatment of multidrug-resistant malaria.

Note: solely a blood schizonticide

Front 7

SE of quinine?

Back 7

**Cinchonism, **hemolysis in G6PD deficiency, and Blackwater fever and positive Coomb's test

Front 8

When do you use mefloquine?

Back 8

DOC for prophylaxis in geographical areas with chloroquine-resistant P. falciparum and alternative drug to quinine in acute attacks and uncomplicated infections resulting form P. falciparum.

Doxycycline is an alternative, so is atovaquone plus proguanil (Malarone)

Front 9

SE of mefloquine?

Back 9

**Mental status change and psychiatric disorders with vivid dreams, dizziness. Also, cardiac conduction defects, neurologic symptoms.

Front 10

What drug is a tissue schizonticide (kills schizonts in the liver) and limits malaria transmission by acting as a gametocide? What its MOA?

Back 10

Primaquine, which acts as an oxidant.

Front 11

What is primaquine used for? And its SE.

Back 11

Hepatic forms of P. vivax and P. ovale.

SE is acute hemolytic anemia in G6PD-deficient PTs. Also, methemoglobinemia.

Front 12

Drug used in exoerythrocytic cycle of malaria

Back 12

Primaquine, therefore, recommended for terminal prophylaxis of P. vivax and P. ovale infections.

Front 13

What is the MOA of

Sulfonamides

Proguanil

Pyrimethamine and cycloguanil

Back 13

Act as antimetabolite of PABA and block folic acid synthesis by inhibiting dihydropteroate synthase.

bioactivated to cycloguanil

Selective inhibitors of protozoan dihydrofolate reductases.

Front 14

What are some antifolate group used to treat blood schizonticides that act mainly against P. falciparum?

Back 14

Pyrimethamine, proguanil, sulfadoxine, and dapsone.

Front 15

What are other antimalarial drugs?

Doxycycline

Amodiaquine

Atovaquone

Halofantrine

Artesuanate, artemether, dihydroartemisinin

Back 15

Doxycyline: chemoprophylactic with chloroquine and mefloquine-resistant P. falciparum

Amodiaquine: in many countries, used for chloroquine-resistant strains of P. falciparum. Can cause agranulocytosis and aplastic anemia.

Atovaquone: part of Malarone, disrupts MT electron transport in protozoa. Malarone is effective for chemoprophylaxis and treatment of P. falciparum

Halofantrine: against erythrocytic stage of all 4 species. QT prolongation.

Artesuanate, artemether, dihydroartemisinin: artemisinin derivatives are metabolized in the food vacuole of parasite forming toxic free radicals. The artemisinins are the only drugs reliably effective against quinine-resistant strains.

Front 16

Drug used as sole agent for treatment of asymptomatic amebiasis?

Back 16

Diloxanide.

Front 17

For mild to severe intestinal infection, what agent is recommended in amebic liver abscess along with a luminal agent and other extraintestinal diseases?

Back 17

Metronidazole or tinidazole

Front 18

DOC for severe intestinal wall disease and in hepatic abscess and other extraintestinal amebic disease such as Giardia lamblia and Trichomonas vaginalis?

Back 18

Metronidazole

Front 19

Metronidazole is effective against?

Back 19

Anaerobic bacteria (Clostridium and Bacteroides species) and protozoans (Giardia, Entamoeba, Trichomonas, and Gardnerella vaginalis).

Also, H. pylori

Front 20

MOA of metronidazole? SE?

Back 20

Reductive bioactivation of its nitro group (by ferredoxin, which is present in anaerobic parasites) to form reactive cytotoxic products to damage DNA and lead to cell death.

Metallic taste, disulfiram-like effect with alcohol. Potentiates actions of anticoagulant drugs. Metro is increased by cimetidine, decreased by phenytoin and phenobarbital.

Note: tinidazole has similar adverse effect, but may be better tolerated than metronidazole.

Front 21

Nitazoxanide treats?

Back 21

DOC: Giardia lamblia and Cryptosporidium parvum.

Can be used for other protozoans (including Entamoeba) and helminths

Note: used only in immunocompetent PTs

Front 22

Primaquine and clindamycin is an alternative drug regimen for?

Back 22

Pneumocystis jiroveci pneumonia

Front 23

TMP-SMX is the DOC for? SE?

Back 23

P. carinii/ jiroveci pneumonia, Isospora belli, and against toxoplasmosis.

Prophylaxis in AIDS PTs (started when CD4 < 200).

Also used for UTI (e.g., E. coli)

Steven-Johnson syndrome, hemolytic anemia (in G6PD), granulocytopenia, kernicterus, nephrotoxicity.

Note: Coadminister folinic acid to prevent anemia without effecting its antibacteiral effect.

Front 24

Combination of pyrimethamine with sulfadiazine have synergistic activity and is the DOC against?

Back 24

Toxoplasma gondii, and is the DOC for this. Clindamycin can be substituted if allergic to sulfadiazine. It can also be used for treatment (with quinine) in areas of chloroquine-resistant P. falciparum. It inhibits tetrahydrofolate.

Front 25

Artemether & artesunate are used for?

Back 25

Alternative for severe chloroquine resistant malaria

Front 26

Doxycycline can be used for?

Back 26

Prophylaxis as an alternative to mefloquine

Front 27

SE of chloroquine?

Back 27

Color vision changes, retinal damage, pruritus

Front 28

What makes up Malarone that can be used for chemoprophylaxis of chloroquine-resistant malaria and protective against mefloquine-resistant falciparum strains.

Back 28

Atovaquone (quinone derivative) with proquanil

Front 29

Pentamidine is a second line drug against what two agents? SE?

Back 29

Pneumocystis carinii (TMP-SMX is first line) in AIDS PTs and Alternative to suramin for African Sleeping Sickness (Trypanosoma rhodesiense and Trypanosoma gambiense)

Note: does not cross BBB, therefore, cannot be used for later stages of trypanosomiasis.

Also, alternative treatment of T. brucei infection.

Diabetes, pancreatitis, hypoglycemia, hypotension, metallic taste, cardiac arrhythmias, anemia

Front 30

Melarsoprol is the DOC for what, and what is its MOA?

Back 30

African sleeping sickness with neurological involvement (late T. brucei infection) since the drug enters the CNS and is a arsenical that inhibits enzyme sulfhydryl groups.

Front 31

Nifurtimox is the DOC for? MOA?

Back 31

American trypanosomiasis (T. cruzi).

Inhibits trypanothione reductase in parasites.

Note: Is the alternative agent in African form of the disease.

Front 32

What is the DOC for early hemolymphatic stages of African trypanosomiasis (trypanosoma brucei rhodesiense and Trypanosoma brucei gambiense) (before CNS involvement) and is also an alternative treatment to Ivermectin in the treatment of Onchocerca volvulus

Back 32

Suramin

Front 33

DOC for leishmaniasis.

Back 33

Stibogluconate. Kills the parasite by inhibition of glycolysis or effects on nucleic acid metabolism.

It is potentially cardiotoxic (QT prolongation)

Front 34

DOC for Giardia lamblia and Trichomonas vaginalis?

Back 34

Metronidazole

Front 35

DOC for American trypanosomiasis (Typanosoma cruzi) (Chagas disease)?

Back 35

Nifurtimox

Front 36

Question: What is recommended for an acute attack of P. vivax?

Back 36

Chloroquine, but will not eradicate exoerythrocytic forms of the parasite.

Front 37

Question: What drug should be given later to eradicate schizonts and latent hyponozoites in the PT's liver?

Back 37

Primaquine (a tissue schizonticide)

Front 38

Question: A PT with lower abdominal discomfort, flatulence, and occasional diarrhea is diagnosed with an intestinal amebiasis, E. histolytica. Oral drug is given to reduce his symptoms. Later, presents with severe dysentery, RUQ pain, weight loss, fever, and enlarged liver. Amebic liver abscess is diagnosed. He has a recent history of drug treatment for a tachyarrhythmia.

The preferred treatment he should have received for initial symptoms (indicative of mild to moderate disease) is?

Drug regimen most effective in treating severe extraintestinal disease in this PT is?

Back 38

Metronidazole (used for mild to moderate amebic colitis), while diloxanide (or iodoquinol) can be used for asymptomatic infection.

Metronidazole plus diloxanide (Effective in most cases of hepatic abscess and dual advantage of being both amebicidal and active against anaerobic bacteria).

Front 39

Question: What is the drug that is antimalarial agent most commonly associated with acute hemolytic reaction in PTs with glucose-6-phosphate dehydrogenase deficiency?

Back 39

Primaquine

Also: dapsone

Antimalarial drugs (chloroquine); Sulfonamides; thiazolesulfone, methylene blue and naphthalene; non-sulfa antibiotics (nalidixic acid, nitrofurantoin, isoniazid and furazolidone)

Front 40

Question: After backpacking in the mountains, the PT develops diarrhea. He did drink from a stream water without purification and is showing symptoms of giardiasis. Since laboratory detection of cysts or trophozoites in the feces can be difficult, you decided to treat with?

Back 40

Metronidazole is the DOC for Giardia lamblia. (tinidazole is equally effective)

Front 41

Question: This drug can clear trypanosomes from the blood and lymph nodes and is active in the late CNS stages of African sleeping sickness.

Back 41

Melarsoprol, since it enters the CNS unlike pentamidine or suramin.

Front 42

Question: Metronidazole is effective against?

Back 42

Amebiasis, bacteroides fragilis, pseudomembranous colitis, and trichomoniasis

Front 43

What drug is recommended as the agent of choice for oral treatment of uncomplicated malaria caused by chloroquine-resistant P falciparum?

Back 43

Quinine, and used in combination with other antimalarial drug such as doxycycline, clindamycin, or pyrimethamine plus sulfadiazine.

Front 44

Question: A traveler in a geographical region where chloroquine-resistant P falciparum is endemic used a drug for prophylaxis but nevertheless developed a severe attack of P vivax.

The drug taken for chemoprophylaxis was?

Back 44

Mefloquine

Alternative: doxycycline, as is atovaquone plus proguanil (Malarone).

Front 45

Question: Plasmodial resistance to chloroquine is due to?

Back 45

Decreased accumulation of the drug in the food vacuole.

Front 46

Question: Proguanil is an inhibitor of ?

Primaquine is the drug that destroys?

TMP-SMZ is the DOC for?

Back 46

Dihydrofolate reductase

Secondary exoerythrocytic schizonts

Pneumocystis jiroveci and toxoplasmosis

Front 47

Which antimalarial drug causes a dose-dependent toxic state that includes flushed and sweaty skin, dizziness, nausea, diarrhea, tinnitus, blurred vision, and impaired hearing?

Back 47

Quinidine

Note: these are dose dependent symptoms of alkaloids (quinine, quinidine)

Front 48

What are sporonticides (proguanil, pyrimethamine) used for?

Back 48

Prevent sporogony and multiplication in the mosquito

Front 49

What makes up Fansidar and used for treatment of chloroquine-resistant forms? What are the SEs?

Back 49

Pyrimethamine with sulfadoxine

Bone marrow depression, hemolysis, kidney damage, folic acid deficiency.

Front 50

Prevention of malaria in travelers:

Chloroquine

Mefloquine

Multidrug-resistant malaria?

Primaquine

Back 50

Prophylaxis in regions without resistance to P. falciparum

Regions with P. falciparum resistance to chloroquine

Doxycycline or Malarone (atovaquone plus proguanil

Terminal prophylaxis of P. vivax and P. ovale

Front 51

What are the tissue amebicides that can on organisms in the bowel wall and the liver?

What are luminal amebicides that act only in the lumen of the bowel?

Back 51

Chloroquine, emetines, metronidazole, tindidazole

**Diloxanide furoate, iodoquinol, paromomycin

Front 52

What is emetine used for?

Back 52

Backup drug for treatment of severe intestinal or hepatic amebiasis.

Is restricted to use in severe amebiasis when metronidazole cannot be used

Front 53

Iodoquinol is used for?

Back 53

Alternative to diloxanide for mild to severe intestinal infections.

Front 54

What is paromomycin used for?

Back 54

An aminoglycoside used for luminal amebicide and may be superior to diloxanide in asymptomatic infection.

Note: diloxoanide is the DOC for asymptomatic infections!

Front 55

What is nitazoxanide used for?

Back 55

G. lamblia and Cryptosporidium parvum.

Note: Nitazoxanide appears to have activity against metronidazole-resistant protozoal strains.

Front 56

Atovaquone is used for?

Back 56

Inhibits MT electron transport and probably folate metabolism.

Less effective than TMP-SMX or pentamidine, but is better tolerated. Used in combination with proquanil (as Malarone).

Front 57

Eflornithine is used for?

Back 57

Some forms of African trypanosomiasis.

Suicide substrate of ornithine decarboxylase.

Front 58

What is cinchonism and blackwater fever associated with quinine?

Back 58

Cinchonism:
Ears: tinnitus, vertigo
Eyes: visual disturbances
GI: nausea, vomiting, etc.
CNS: headache and fever

Blackwater fever: massive lysis of RBCs, causing dark urine with hemoglobinuria, renal failure, intravascular coagulation, and possibly death.

Front 59

SE of doxycycline?

Back 59

Photosensitivity, stains permanent teeth and inhibits bone growth. Do not use in children less than 8 years of age, or in pregnant women!

Front 60

When considering risk/benefit analysis, what is the DOC for malaria during pregnancy?

Back 60

Quinine and clindamycin