anti-helminthic drugs Flashcards Preview

Pharm > anti-helminthic drugs > Flashcards

Flashcards in anti-helminthic drugs Deck (38):
1

what are the anti-helminthic drugs

mebendazole
albendazole
pyrantel pamoate
diethylcarbamizine
ivermectin
praziquentel

2

drugs that are used for GI infections are characterized by:

designed to be poorly absorbed by the GI tract to reduce possible systemic toxicity to host

toxicity is usually confined to localized irritation of the GI tract
primary excretion is through the feces

stimulate mass migration of the works in the GI tract causing intestinal or bile duct obstruction that may surgical intervention

a purge may be necessarily adminstered with anti-helminthic in order to flush the work from the GI tract

if they aren't rapidly flushed, the partially digested female works can invade the intestinal wall and develop larvae (cystercosis)

3

what are the three categories of parasitic worm infections

tape worms (cestodes)

flukes (trematodes)

nematodes (round worms)

4

the four cestode organisms are:

taenia solium (pork tape worm)
taenia saginata (beef tapeworm)
hymenolepis nana (dwarf tapeworm)
diphyllobothrium latum (fish tape worm)

beef and pork widespread
fish mostly in europe
dwarfm more prevalent in tropical climates

5

what drugs are used to treat tapeworm infections

praziquantel
albendazole is drug of choice for cyst larvae of T solium

6

the three blood flukes (trematodes) are

schistosoma haematobium (africa)
schistosoma mansoni (africa, america)
schistosoma japonicum (far east)

7

the liver flukes are -

trematodes

clonorchis sinesis
- encysted larvae from raw fish

inflammation and deformation of bile duct, hepatitis, anemia, edema

8

the lung flukes are

trematodes

paragonimus westermani
- encysted larvae in crab meat
cough (dry, rusty brown sputum)
pulmonary pain, pleurisy

9

the drug of choice against schistosomaisis (trematodes)

praziquantel

10

the nematodes that infest the GI tract are

ascaris lumbricoides
trichuris trichiura (whip worm)
nector americanus, ancyclostoma duodenal (hook worms)
strongyloides stercoralis (threadworm)
enterobuius vermicularis (pinworm)

11

the nematodes that cause systemic infection are

trichinella spiralis
wuchereria bancrofti
onchocerca volvulus

12

found in warm climates of southern us
lower SES have high incidence due to poor sanitation

ascarius lumbricoides

13

cause daily blood loss and resulting iron deficiency and anemia
new world - most common in americas, central and southern africa, southern asia, indonesia, australia, pacific islands
old world - dom species in mediterranean region and northern asia
hookworms

necator americanus (new world)
ancyclostoma duodenale (old)

14

found in warm humid climates world wide
infection more common in children and found where infection and ascaris and hook worm can occur
obstruction of appendix may occur in seriously infected patients
whipworm

trichuris trichiura

15

found in southern parts of US
occasionally found in mines and caves
thread worm

strongyloides stercoralis

16

most common worm infestation of children in US
no SES or geographical barriers
pinworm or seat worm

enterobius (oxyuris) vermicularis

17

infects 1-4 percent of US population
due to eating raw or undercooked pork containing encysted larvae
nausea, vomiting, diarrhea, ab pain, headache, muscle pain
tachycardia, vascular thrombosis, mental apaty, delirium, coma

trichinella spiralis

18

systemic infection to lymphatics, brain, eye
rarely in US, more common in Med region, south pacific, africa
lymphadenitis due to inflam response to the parasite lodged in lymphatic channels and tissue
as worm dies, reaction continues and produces granuloma --> lymph edema, elephantiasis

wuchereria bancrofti

19

infects eye, skin, lymphatics,
nodular lesions
photophobia, lacrimation, blindness

onchocerca volvulus

20

drug of choice for t. trichuria (gi nematode)

mebendazole

21

drug of choice for cysticercosis due to T solium

albendazole

22

drugs that treat GI nematodes

mebendaozle * choice
albendazole
pyrantel pamoate

23

drug of choice for e vermicularis (pinworm, GI nematode)

pyrantel pamoate

24

what drugs treat systemic namtodes

diethylcarbamazine
ivermectin

25

which drug treats systemic nematodes and also s stercoralis (GI nematode)

ivermectin

26

mebendazole, albendazole - mechanism

inhibits glucose uptake and uncouples oxphos
causes immobilization, death, and expulsion from the GI tract

27

mebendazole - use

broad spectrum - GI nematodes
drug of choice for t. trichiura

28

albendazole - use

absorption is enhanced with fatty food
braod spectrum for Gi nematodes
drug of choice for cysticercosis due to T solium
not effective against larvae in tissues of T spiralis (systemic nem) but is effective against GI phase

29

pyrantel pamoate - mechanism

depolarizing neuromuscular blocking agent
causes persistant activation of nicotinic acetylcholine receptors
results in worm paralysis and removal by gut peristalsis

30

pyrantel pamoate - uses

drug of choice for E vermicularis (GI nem)
not as effective for other nematode infections

31

praziquantel - mechanism

increases parasite permeability to Ca2+
causes severe muscle contractions
directly kills adult schistasomes
dislodges cestodes from their usual sites of attachment in the intestine

32

praziquantel - uses

broad spectrum - schistomaniasis and cestodes in the GI tract
(effective but not the drug of choice for cyst larvae of T solium)


metabolized by p450
containdicated in patients with ocular cysticercosis due to eye damaging host response

33

praziquantel - drug interactions

macrolides and HIV proteases increases praziquantel concentration in serum

34

diethylcarbamazine - mechainsm

sensitizes worms to phagocytosis by macrophages

35

diethylcarbazine - uses

systemic nematodes (w bancrofti, o volvulus)

36

diethylcarbazine - toxicity

mazzottis reaction

37

ivermectin - mechanism

opens chloride channels (glutamate and GABA gated channels) in invertebrates causing paralysis of muscles (mammalian muscles dont have these channels)

38

ivermectin - use

w bancrofti
o volvulus (systemic

s stercoralis (gi nematode)