ANTIHELMINTIC DRUGS

ANTIHELMINTIC DRUGS :

Roundworms
A.LUMBRICOIDES
E.
VERMICULARIS
ROUNDWORM
PINWORM
N. AMERICANUS
T. TRICHURA
HOOKWORM
WHIPWORM
S. STERCORALIS
THREADWORM
Tissue Nematodes
ONCHOCERCA
Wuchereria
bancrofti
ANCYCLOSTOMA
DRUGS THAT ACT AGAINST NEMATODES
A.ALBENDAZOL E
MECH OF ACTION – blocks glucose uptake in
both larval and adult parasite , which
leads to decrease formation of atp
-
inhibition of microtubule assembly
CLINICAL USE : broad anthelintic spectrum
first drug of choice for larve migrans(
ancylostoma spc)
alternative drug for roundworms , whipworm,
hookworms,pinworms and threadworm
TOXICITY : reversible leukopenia ,
alopecia and changes in the liver
anzymes
LONG TERM USE : bone marrow suppresion
and fetal toxicity
B. DITHYLCARBAMAZINE
MECHANISM OF ACTION : immobilizes
microfilariae
CLINICAL USE: drug of choice for filariasis
alternative for onchocerciasis ( in
combination with suramin)
TOXICITY : headache, malaise, weakness,
anorexia
can cause the mazzotti reaction in
onchocerciasis – hypotension, pyrexia
respiratory distress and prostration
fever, rashes and ocular damage
C. IVERMECTIN
MECHANISM OF ACTION : intesifies gaba
mediated neurotransmission in
nematodes resulting to paralysis
CLINICAL USE : drug of choice for
onchocerciasis : drug of first choice for
strongloidiasis and alternative drug for
filariasis
TOXICITY : fever, headache ,dizziness
,rashes, pruritus, tachycardia
,hypotension , joint pains , muscle [ain
and pain ion lymph nodes
D. MEBENDAZOLE
MECHANISM OF ACTION – selctively inhibit
microtubule syntheisi and glucose uptake in
nematodes
CLINICAL USE :
drug of first choice for pinworms ,
whipworms and round worms
second drug of choice for cestodes
nad trematode infection
TOXICITY : only limited to gastrointestinal
irritation . embyrotoxic
E. PIPERAZINE
MECH. OF ACTION – acting as agonist at gaba
recptors
CLINICAL USE ; drug of choice for ascariasis
TOXICITY : git irritation
F. PYRANTEL PAMOATE
MECH OF ACTION – pyrantel pamoate and its
congener axantel pamoate, stimulate
nicotinic receptor present at tne
neuromuscular junctions of nematodes.
contraction of muscle occurs ,followed by
a depolarizarion induced paralysis
CLINICAL USE : ( along with mebendazole)
drug of choice for hookworm, pinworm
and roundworm infestation .
TOXICITY - git distress ,headache and
weakness
TREMATODES
SCHISTOSOMA (BLOOD FLUKE )
LUNG FLUKE
CLONORCHIS SINENSIS(LIVER
FLUKE)
DRUGS THAT ACT AGAINST
TREMATODES
A. PRAZIQUANTEL
MECH. OF ACTION – increases membrane
permeability to calcium, causing marked
contraction initially and then paralysis of
trematode muscles ; this is followed by
vacuolization and parasite death
CLINICAL USE : drug of choice for
schistosomiasis, clornorchiasis and
paragonimiasis
it is also one of the drug of choice for
cestodes
TOXICITY – headache , dizziness, malaise and
git irritation , skin rashes and fever
CONTRAINDICATION : ocular cysticercosis
B. BITHIONOL = drug of choice for the
treatment of fascioliasis ( sheep liver
fluke)
TOXICITY : nausea , vomiting, diarrhea,
abdominal cramps, dizziness, dizziness,
headache , phototoxicity , pyrxia, tinnitus,
proteinuria and leukopenia
C. METRIFONATE – is an organophosphate
prodrug that is converted in the body to
cholinesterase inhibitor dichlorvos , this
active metabolite acts solely against
schistosoma haematobium ( the cause of
bilharziasis )
D. OXAMNIQUINE – effective solely in
schistosoma mansoni infections
TOXICITY : dizziness ,git irritation , pruritus
REACTION TO DYING PARASITES –
eosinophilia ,urticaria and pulmonary
infiltrates
DRUG THAT ACT AGAIST CESTODES
(TAPEWORM)
NICLOSAMIDE
MECHANISM OF ACTION ; act by uncoupling
oxidative phosphorylation or by activating
atpase
CLINICAL USE : effective in beef, pork and fish tapeworm but not in cysticercosis ( albendazole or prqaziquatel is more effective)
TOXICITY ; git distress ,headache, rash and