Antiparasitic/Antimalarial

Question 1

Ivermectin

Answer 1

.

Question 2

Mebendazole

Answer 2

.

Question 3

Albendazole

Answer 3

.

Question 4

Praziquantel

Answer 4

.

Question 5

Chloroquine

Answer 5

MOA: prevents biocrystillization of Hb breakdown product to
hemozoin
Effect: accumulation of heme (toxic to parasite)
Resistance: P. falciparum mutations in PfCRT
DOC: tx of non-falciparum, chemoprophylaxis of vivax and ovale, tx sensitive uncomplicated falciparum, combined w/ Primaquine for vivax and ovale
PK: given weekly, PO
SE: N/V/D, hemolysis (G6PD def), ECG changes
CI: psoriasis or porphyria, eye probs

Question 6

Quinine / Quinidine

Answer 6

MOA: depresses O2 uptake and CHO metabolism
Use: Quinidine IV for severe falciparum, Quinine PO tx of falciparum
SE: QT prolongation, cinchonism (α and M blockade sx’s), HS rxns, hypoglycemia, hemolysis (G6PD), uterine contractions, severe hypotension, Blackwater fever (hemolysis and hemoglobinuria)
CI: pregnancy (Category C), concurrent use of Mefloquine is CI, can raise levels of Warfarin and Digoxin

Question 7

Mefloquine

Answer 7

PK: PO only, weekly dosing
Use: Chloroquine-resistant strains, tx acute infection w/ falciparum and vivax, prophylaxis against falciparum and vivax (can be used in pregnant women in chloroquine-resistant areas)
SE: neuro and psych sx’s
CI: psych disorders, epilepsy, arrhythmias, DO NOT give w/ Quinine, Quinidine or Halofantrine

Question 8

Primaquine

Answer 8

DOC: eradication of liver form of vivax and ovale
Use: acute vivax and ovale, prophylaxis of vivax and ovale, chemoprophylaxis against falciparum and ovale
SE: hemolysis or methemoglobinemia (esp G6PD def pt’s)

Question 9

Malarone

Answer 9

= Atovaquone + Proguanil
MOA: disrupts mitochondrial ETC
PK: PO only
Use: tx and prophylaxis of falciparum
CI: pregnancy

Question 10

Doxycycline

Answer 10

Use: tx for severe falciparum after initial tx w/ quinine or Artesunate, chemoprophylaxis against most forms
PK: daily dosing
SE: discoloration of teeth, photosensitivity
CI: pregnancy and children < 8yo

Question 11

Artemisinin

Answer 11

PK: short t/12
Use: tx for severe falciparum (IV)
SE: neurotoxic and QT prolongation @ toxic doses

Question 12

Clindamycin

Answer 12

Use: antimalarial as alternative to Doxycycline

Question 13

Halofantrine

Answer 13

Use: tx erythrocytic stages of all malaria
CI: pregnancy bc it’s teratogenic

Question 14

Lumefantrine

Answer 14

PK: given in combo w/ Artemether
Use: tx erythrocyte stages of malaria
SE: QT prolongation

Question 15

Folate Synthesis Inhibitors

Answer 15

Pyrimethamine / Proguanil / Sulfadoxine
Resistance: common for falciparum
Use: chemoprophylaxis, intermittent preventative therapy, tx of chloroquine-resistant falciparum (NOT used for severe malaria)

Question 16

Pyrimethamine + Proguanil MOA

Answer 16

MOA: inhibition plasmodia dihydrofolate reductase
Use: act slowly against erythrocytic forms of all malaria species

Question 17

Proguanil

Answer 17

Use: some activity against hepatic forms (safe in pregnancy)
SE: mouth ulcers, alopecia (rare)

Question 18

Sulfonamides action

Answer 18

MOA: inhibit dihydropteroate synthase
Use: weakly active against erythrocytic schizonts
SE: hematologic, GI, CNS, derm and renal toxicity

Question 19

Pyrimethamine-Sulfadoxine SE

Answer 19

Erythema multiforme, Steven-Johnson syndrome