1. Presented By
Dr. Manoj Kumar
Assistant Professor
Department of Pharmacology
Adesh Medical College & Hospital Ambala Can’t
2. Helminthes; means worms
Prevalent globally; 1/3rd of world population infected.
But, more common in developing countries with poorer
personal and environmental hygiene.
They are commonly transmitted through feco-oral
route.
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3. Clinical symptoms arise mainly due to the toxins
production.
Acute or chronic blood loss leading to anemia.
Diarrhoea, Dysentery.
Abdominal pain
Subcutaneous nodules
Allergic Reactions, Urticaria
Injury to visceral organs
Intestinal or lymphatic obstruction
Conjunctivitis, Retinitis, Blindness
Hepatosplenomegaly
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11. Mebendazole, Albendazole, Thiabendazole
Against nematodes, cestodes including larva migrans
MOA
Inhibit polymerization of β-tubulin
Inhibit glucose uptake
Deplete glycogen stores
Death
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12. Mebendazole is a synthetic benzimidazole.
Introduced in 1972
Broad spectrum of anthelmintic activity & a low
incidence of adverse effects.
It is a drug of choice in the treatment of infections
by whipworm eggs, pinworm, hookworms, and
roundworm.
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13. Memendzol
Bind to β tubulin of parasite
Inhibit polymerization
Inhibit synthesize to microtubule
Decrease several metabolic activity of parasite
Inhibit glucose uptake in parasite
Inhibit glycogen storage.
Parasite death
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14. Minimal absorption in intestines.
Less than 10% of orally administered is absorbed.
The absorbed drug is bound to protein (> 90%), rapidly
converted to inactive metabolites.
Fatty food enhance absorption.
Half -life of 2-6 hours.
75 – 90% of oral dose passed in the faeces.
Dose: – 100 mg chewable tablet.
- 100 mg/5ml suspension.
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15. Roundworm
Hookworm
Whipworm
10 mg twice a days for 03 consecutive
day. No fasting, purging or any other
preparation of the patient is needed.
Pinworm
100 mg single dose repeated after 2-3
weeks (to kill the ova that have develop to
later.
Trichinosis
200 mg BD for 04 days less effective then
albandazole.
Hydratid disease
200-400 mg BD or TDS for 3-4 weeks,
less effective then albandazole.
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16. Well tolerated even by patient in poor health.
Mild- nausea, vomiting, diarrhea, and abdominal pain have
been reported infrequently.
High-dose hypersensitivity reactions (rash, urticaria),
granulocytopenia, alopecia, and elevation of liver enzymes.
Teratogenic in animals,
Contraindicated in pregnancy and in children 2yr. of age
because of rare reports of convulsions in this age group.
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17. It is a prodrug congener of memendazole.
Broad spectrum anti-helminthic
PK
◦ Fatty meals increase absorption
◦ Wide distribution in tissues, bile, CSF, hydatid cyst
◦ Active metabolite, t1/2: 8-12 hrs
◦ Given empty stomach for intestinal worms
Dose: 400 mg, single dose regime
Weak microfilaricidal action, kills cysticerci, hydatid larvae
Good antihelminthic activity in tissues
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18. The active metabolite of albendazole is achieve a higher
concentration(100 times more) then memendazole.
Albendazole is better tolerated.
Effective is single dose in most infections.
Superior to memendazole in the treatment of infections
by threadworm, pinworm, hookworms, hydatid disease,
filariasis and roundworm.
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19. Miner and similar to memendazole nausea, vomiting,
diarrhea and abdominal pain .
High-dose jaundice, fever, weakness, hypersensitivity
reactions (rash, urticaria), alopecia, insomnia
Teratogenic in animals
Avoided in pregnancy.
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20. Fist broad spectrum anthelmintic agent.
Inhibit development of eggs of worms and kills larva apart
of all intestinal.
Rapidly absorbed
Half- life of 1-2 hrs
Completely metabolized in liver
90% is excreted in urine
Can also absorbed through skin.
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21. More toxic than other benzimidazoles
GI disturbances
Purities, headache, drowsiness, psychoneurotic symptoms.
Irreversible liver failure.
Stevens –Johnson syndrome
Not used in young children , pregnancy, hepatic and renal
diseases.
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22. Introduced in 1969 for pinworms infection in children.
Son extended against roundworm, hookworm.
Efficacy again – ascaris, enterobius and ancylostoma is
high and comparable to memendazole
Neuromuscular blockade
Only small proportion absorbed from GIT
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23. Pyrantel pamoate
Stimulate nicotinic cholinergic receptor in the worm
Persistent depolarization
Inhibits cholinesterase
Spastic paralysis of worm
Unable to attach to intestinal wall
Paralysed worms are expelled
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24. Adverse effects:
Infrequent mild GI disturbance
Drowsiness, headache, insomnia, rash, fever
Contraindications & Cautions
Liver dysfunction.
Pregnancy
Children under 2 years of age
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25. Only recommended for the treatment of ascariasis
Cure rate 90% for 2 days treatment.
Readily absorbed orally and excreted unchanged in urine
MOA:
Paralysis of ascariasis by blocking Ach at myoneural
junction.
Treatment is continued for 3-4 days or repeated after one
week in case of heavy infections.
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26. GI disturbance.
Neurotoxicity, allergic reactions .
Contraindications
Epilepsy or a history of epilepsy.
Impaired liver or kidney functions.
Pregnancy.
Chronic neurologic disease.
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27. Second-line drug for treatment of most tapeworm
infections like Taenia saginata, T.salium, H.nana and
pinworm.
Mechanism of action:
Adult worm( not ova) is rapidly killed by inhibition of
oxidative phosphorylation.
Pharmacokinetics:
Poorly absorbed from gut & excreted in urine.
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28. Treatment of most forms of tapeworms.
Not effective against cysticercosis or hydatic
disease.
Given in the morning on empty stomach.
Purgative is necessary to purge all dead segments
& prevent liberation of ova.
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29. Mild, infrequent GI disturbance
Alcohol consumption should be avoided
Not indicated in children under 2 yrs of age or in
pregnancy.
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30. MOA
Rapidly taken up by worms
Leakage of intracellular Ca++ causing paralysis
Worms lose grip on intestinal wall including tissues and
veins.
Acts against all stages of worms including larvae
ADRs –
Drowsiness, Dizziness, Urticaria.
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31. Drug of choice for the treatment of filariasis and tropical
eosinophilia.
Pharmacokinetics:
Rapidly absorbed from gut
Half- life is 4-12 hours
The drug should be given after meals
It is excreted in urine as unchanged forms.
Dosage is reduced in urinary alkalosis and renal impairment.
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32. Immobilizes microfilariae and alters their surface
structure,
Displacing from tissues & making them susceptible
to destruction by host defense mechanism.
It has immunosuppressive effects
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33. Fever, malaise, head ache, loss of appetite, GI disturbance,
cough, Chest pain, weakness, dizziness, rash, pruritus,
enlargement of lymph node, bronchospasm, fall BP and
joint pain.
Leucocytosis
Retinal hemorrhage
Encephalopathy
C/I: Hypertension, Renal disease, pregnancy.
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34. Ivermectin is a semi synthetic analog of avermectin B
obtained from streptomyces avermitilis.
Given only orally.
Rapidly absorbed.
Does not cross BBB.
Half- life is 16 hrs.
Excretion in feces.
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35. Acts on the parasites glutamate-gated Cl- channel
receptors
Chloride influx increased, hyperpolarization occurs ,
resulting in paralysis of the worm.
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36. Drug of choice for cutaneous larva migrans &
strongyloidiasis.
It is also used for scabies, lice .
Filariasis.
Onchocerciasis
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37. Mild - Fatigue, dizziness, nausea, abdominal pain,
constipation, lethargy and ECG changes.
Killing of microfilaria result in a Mazotti reaction
( fever, Urticaria, headache, hypotension,
tachycardia, peripheral edema)
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38. Use with other drugs that enhance GABA e.g
Barbiturates, bnzodiazepines, valproic acid.
Pregnancy
Meningitis
Children under 5 years of age.
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39. MOA: Neuromuscular blockade
Status
◦ Used only in ascaris, hookworm infestation
Also a immunomodulator
◦ Restore depressed T cell functions
◦ Useful in vitiligo, oral ulcers
Adverse effects
◦ Nausea, vomiting, abdominal discomfort, headache
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41. Caused by the louse Pediculus humanus.
Lice can infest scalp, body or pubic region.
Drugs used:
1. Permethrin 1% lotion or cream is rubbed over
the scalp, allowed to remain for 10 minutes and
then washed off.
2. Ivermectin (200 ug/kg) may be used orally as a
single dose.
3. DDT 2% lotion, gammaxane 2% shampoo,
malathion 0.5% lotion
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