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Flashcards in Anti-Parasitic therapy Deck (26):
1

Tinidazole

toxicities:

dosing:

Uses:

toxicities:

Similar toxicities to Metronidazole

dosing:

More convenient dosing schedule

Oral only

Not FDA indicated for anaerobic infection, would not use for this purpose

Used for:

Amebiases

Trichomoniasis (relaspe or 2nd attempt, reinfection)

Giardiasis

2

Iodoquinal

mech:

absorption:

adverse:

spectrum

mech: unknown

absorption:

- poorly absorved oral formulation

- active in intestinal lumen

adverse:

nasuea, vomiting, rashes

spectrum:

-amebiasis tx only

- followup tx for severe amebiasis after a course of metronidazole

3

Nitazoxanide

mech:

admin:

adverse:

 uses:

Mech:

interferes with electron transfer necessary for anaerobic metabolism

Admin:

oral only

Adverse:

Gi upset, headache

uses:

giardiasis

cryptosporidiosis

C. difficile

Hep C

 

not first line, expensive and not more effective that metro

4

Trypanosomiasis TX

T cruzi:

- nifurtimox (CDC only)

-Benznidazole (CDC only)

- available in South america

T. brucei gambiense:

- pentamidine or suramin (dont memorize)

- need CDC approval

- late disease treated with eflornithine and nifurtimox

T. Brucei rhodesiense: (dont memorize)

- suramin or melarsoprol

 

5

Chloroquine

Malaria chmoprophylaxis

- Quinacrine

- inhibits polymerization of hemozoin in PLasmodium food vacuole

- inexpensive

- only weekly dosing

- AEs: itching in Africans, vomiting, rashes

Widespread resistance of P. Falciparum

- Efflux pump reduces concentraiton in food vacuole

- REsistance restricts to select areas

6

Mefloquine (Larium)

- later generation quinacrine

- dosed weekly

- active against chloroquine reistant malaria

- Toxicities: vertigo, lightheadedness, neuropsychiatric (nightmares, psychosis, suicide)

 

better drugs avavilable

7

Doxycycline

dosed daily

Malaria prophylaxis

increased sun sensitvitiy, Gi upset not for children, pregrant women (staining of developing teeth)

8

Malaria self tx

Atovaquone proguanil

Mefloquine

Artemesinins

Less use of pyrimethamine sulfadoxine due to resistance, toxicities

rapid diagnostic tests on rise

9

Pryantel pamoate

Tx of pinworm, hookworm

Toxicities: GI upset, dizziness

Vet use

10

Lice, scabies (ectoparasites)

topical tx:

systemic tx:

topical:

- permethrin (Elimite, nix), insect neurotoxin

- Malathion

Systemic:

- ivermectin

11

summary

Metronidazole use for protozoa

Praziquantel, mebendazole, abendazole, ivermectin for worms

12

Ivermectin

uses:

Tx for:

- ascariasis, toxocariasis, cutaneous larva migrans

- onchocerciasis

- some filaria

- lice

13

Antiprotozoal treatments

metronidazole, tinidazole

iodoquinol

paromomycin

nitazoxanide

14

Metronidazole

mech:

distribution:

spectrum:

adverse:

Mech: Acts as an electron acceptor, once activated by reduction, it damages DNA and other macromolecules

Distribution:

penetrates well into all tissues

Spectrum:

highly bactericidal for anaerobic bacteria

protozoan infections:

trichomoniasis

Giardiasis

Amebiasis

Adverse:

beware of disulfiram-like reactions, metallic taste, neuropathy with prolonged use

15

Paromomycin

mech:

admin:

adverse:

uses:

mech:

proteins synthsis inhibitor, binds16s ribosomal RNA

admin:

oral only

adverse:

nausea, diarrhea, abdoinal pain

Uses:

amebiasis

alternative tx for leishmaniasis

16

Toxoplasmosis tx

-prophylaxis of reactivation in AIDS:

-treatment with ____ + _______.

trimethoprim sulfamethozazole- prophylaxis in AIDS patients

treament with prymethamin + sulfadiazine or clindamycin or atovaquone

17

Leishmaniasis

-visceral

1. Liposomal amphotericin B (ergosterol in cell membrane)

2. Sodium stibogluconate (pentavalent antimony)

3. Paromomycin is an alternative

18

Atovaquone proguanil (malarone)

Malaria prolaxis

- expensive

- dosed daily

- atovaqone inhibit mitochondrial electron transport

- proguanil acts as a DHFR inhibitor

- toxicities: Gi upset, rash, well tolerated

19

Malaria tx

- uncomplicated for mild P. falciparum

atovaquone proguanil

artemther/ lumafantrine (coartem)

Artesunate (CDC)

20

Artemesinins

- tx of malaria

- chinese herbal derivatives- qinghaosa

- monotherapy not recommended

- emerging reisistence in SE asia

21

Quinine

tx of malaria

- quinine sulfate + doxycyline or clindamycin

Toxicity: flushing, tinnitus, confusion, cardiac conduction

- Mefloquine

22

Tx for severe Malaria

P. Falciparum

- quinidine gluconate IV

- Quinine dihyrdochloride IV

- plasma exchange in severe cerebral malaria

- close monitoring of volume status to avoid pulmonary edema due to capillary leak syndrome

23

Tx of P. vivax

reactivation prevented by followup tx with primaquine to kill hypnozoite stage in liver

- check GPD level to exclude deficiency prior to use to avoid hemolysis

 

24

praziquantel

 

Antihelminthic tx

- unknown mech

- toxicities: GI upset, ab pain, rash

- tx of: schistosomiasis, chlonorchiasis, other flukes (not Fasiolahepatica)

25

Albendazole, Mebendazole

mech: inhibit tubulin polymerization, microtubule formation in worms

toxicities: GI upset, headache

Uses:

- pinworm, whipworm, hookworm, ascariasis

- echinoccocus, cysticercosis, trichinosis

- strongyloidiasis, toxocariasis, cutaneous larva migrans

- filaria

26