(Mode of Action of Drugs)
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Chapter
1.4
Chapter
9.10 Anthelmintic Agents
Anthelmintic agents are used to eradicate
(either kill or expel) the infesting helminths.
The important anthelmintic agents
along with their specific uses and dosage
are listed in table 9.10.1.
MEBENDAZOLE
It is a synthetic benzimidazole having
a wide spectrum of anthelmintic activity.
After administration it is poorly absorbed
and approximately 90 percent of the drug
is passed in faeces. Complete clearance of
the parasites from the GIT may take up to
three days.
Mebendazole binds to microtubular
protein ‘βββββ tubulin’ of parasite and inhibits
its polymerization, thus irreversibly
impairing glucose uptake.
Adverse effects include nausea,
diarrhoea, abdominal pain. Alopecia and
granulocytopenia may occur at high
doses.
ALBENDAZOLE
Congener of mebendazole. It is given
only as single dose.
Poorly absorbed from the GI tract, oral
bioavailability being enhanced when given
with a fatty meal (up to 5 fold). Its active
sulphoxide metabolite is widely distributed
throughout the body and is excreted in
urine.
Adverse effects include nausea,
vomiting, epigastric distress, abnormal
LFTs, reversible alopecia.THIABENDAZOLE
Apart from anthelmintic property, thia-
bendazole also possesses antiinflammatory,
analgesic and antipyretic actions. It also in-
hibits development of eggs of worms and
kills the larvae.
It is rapidly absorbed, metabolised by
hydroxylation and conjugation to inactive
metabolites and excreted through kidney.
Adverse effects include nausea, vomiting,
skin rash, anorexia, giddiness, abdominal
pain, diarrhoea, fever and headache.LEVAMISOLE
It is a synthetic imidazothiazole
derivative and is highly effective in