TC5-G--Protozoal Infections

Question 1

Metronidazole

Answer 1

Free radical damage to bacterial DNA/proteins
Tx: E. histolytica, D. fragilis, Giardia, Trichomonas
SE: seizures (rare), metallic taste, nausea, vomiting, disulfiram-like rxn
–C/I– don’t give to pregnant pt’s

Question 2

Tinidazole

Answer 2

Free radical damage to bacterial DNA/proteins
Tx: E. histolytica, Giardia, Trichomonas
SE: metallic taste, nausea, vomiting, disulfiram-like rxn

Question 3

Iodoquinol

Answer 3

Unknown MOA
Tx: E. histolytica, D. fragilis
SE: iodine toxicity, GI upset, rash
–CAUTION– pt’s with optic neuropathy, renal dz, thyroid dz

Question 4

Diethylcarbamazine

Answer 4

Arachidonic acid metabolism inhibitor
Tx: Loa Loa, lymphatic filariasis
SE: “Mazzotti reaction” when used in onchocerciasis: fever
pruritis, rash, hives, lymphadenopathy, tachycardia, arthralgia, headache

Question 5

Pentamidine

Answer 5

Inhibits ox. phosphorylation; interferes with DNA/RNA fxn
Tx: T.b. gambiense (early infection)
SE: pancreatitis, nephrotoxicity

Question 6

Melarsoprol

Answer 6

Inhibits ATP synthesis
Tx: T. b. rhodesiense (late infection)
SE: arsenic poisoning: seizures, encephalopathy, neuropathy, fever, rash
–C/I–G6PD deficiency

Question 7

Nifurtimox

Answer 7

Unknown MOA
Tx: T. cruzi
SE: polyneuropathy, GI symptoms, anorexia, vertigo, headache, insomnia

Question 8

Albendazole

Answer 8

Microtubule synthesis inhibitor (binds beta-tubulin colchicine site)
Tx: A. duodenale, N. americanus, E. vermicularis, T. spiralis, T. trichiura, Ascaris, E. granulosus; 2nd line– loa loa, S. stercoralis, clonorchis
SE: Bone marrow suppression, hepatotoxicity, hair loss, GI symptoms

Question 9

Mebendazole

Answer 9

Microtubule synthesis inhibitor
Tx: A. duodenale, N. americanus, E. vermicularis, T. spiralis, T. trichiura, Ascaris
SE: GI symptoms, fever, headache, drowsiness

Question 10

Pyrantel Pamoate

Answer 10

Depolarizing NMJ Blocker (binds nACh-R)
Tx: A. duodenale, N. americanus, E. vermicularis
SE: GI symptoms, rash, insomnia

Question 11

Ivermectin

Answer 11

Glutamate-gated Cl- channel binder –> paralysis
Tx: T. trichiura, Ascaris, S. stercoralis
SE: GI symptoms, rash, dizziness

Question 12

Praziquantel

Answer 12

Increased Ca2+ permeability –> paralysis
Tx: Clonorchis, Paragonimus, Schistosomiasis, Taenia, Diphyllobothrium, E. granulosus, cerebral cysticercosis
SE: hepatotoxicity, metabolized by P450, GI and CNS symptoms,

Question 13

Niclosamide

Answer 13

Inhibits ox. phosphorylation, glucose uptake
Tx: Taenia, Diphyllobothrium, cerebral cysticercosis
SE: GI symptoms, rash