Anthelmentics
Introduction:
• Tropical diseases caused by parasitic
worms (multicellular organism) which infest the body are called as helminth.
• The three main families of worms that
infest human being belong to two phyla.
1. Nematodes /nemathelminthes (round worm)
2. Platyhelminthes
i) Cestodes (tape worm )
ii)Trematodes
• Most of the
people carry one or another type of parasite in intestine .among the nematodes,
hook worm causes dangerous infestation as they remains attached to wall of
intestine and suck the blood.
Other nematode
infection are following
i) Safaris (round worm)
ii)Thread worm
iii) Whip worm
iv) Guinea worm
v) Pin worm
vi)Trichinosis
• Cestodes are
unpleasant but do not cause serious illness.
• The
Trematodes infestations contributing to death is Schistomiasis (blood flukes or
bilharzias) is when penetrating the unbroken skin to veins and causing slow
destruction of liver and kidney.
• This parasite
cause abdominal pain, anorexia, diarrhea with blood and mucus, enlarged liver
Definition: – Anthelmentics are the drugs which are used to combat (appose) any type of
helminthiasis (Helmenthic infections)
Classification of Anthelmentics:-
1. Halogenated
hydrocarbon:-e.g. Tetrachloroethylene.
2. Halogenated
phenol and biphenyl:-e.g. Bithinol
3. Dyes: – Gentian
violet
4. Piperazine
and related compound:-e.g. Piperazine citrate, DEC.
5. Other
heterocyclic ring containing compound:-E.g.Mebendazole, (benzimidazole) niridazole
(imidazole).
6. Alkaloids:
– e.g.-Emetine
7. Antimonial
compound:-e.g. –Antimony Potassium Tartarate
Piperazine
Structure of Piperazine:
Properties of Piperazine:-
1. Piperazine
hexahydrate is colourless and glassy with deliquescent crystal having faint
characteristics odour.
2. It is
freely soluble in water and alcohol.
3. Very
slightly soluble in ether.
4. It is
official as its citrate, phosphate and adipate salt.
5. Ii is an
ideal Anthelmentics agent.
6. It is nontoxic
at therapeutic dose level and palatable in conventional formulation
7. It
remains a drug of choice for therapy of ascaris and pinworm.
8. It blocks
the neuromuscular transmission in ascaris at myoneural junction.
9. The worm
is paralyzed and is unable to resist peristalsis and thus expelled with the stool.
Chemical properties of Piperazine:-
• When Aqs.
Solution is treated with potassium fericynide solutions in presence of mercury
and sodium bicarbonate, a red colour slowly produced.
Stability and storage of Piperazine:-
• It is deliquescent
and affected by light .hence it is stored in tightly closed light resistant
containers.
Uses of Piperazine:-
It is used to treat:
1. Pinworm
infestations (enterobiosis)
2. Round
worm infestations (ascariasis )
Pharmaceutical formulations of Piperazine:-
1. Piperazine
citrate elixir.
2. Piperazine
citrate tablets.
Brands names of Piperazine:
1. Antepar
2. Helmacid
3. Wormicid
DEC / diethyl
carbamzine
Structure of Diethyl carbamzine:
Chemical name:-N, N diethyl 4 –methyl Piperazine
-1 carboxamide.
Properties of Diethyl carbamzine:
1. It is official as citrate salt.
2. It is white crystalline powder.
3. It is odourless.
4. It has bitter taste.
5. It is soluble in water
6. It is practically insoluble in
chloroform and ether.
Stability
and storage of Diethyl carbamzine:-
• It is stored in tightly closed
containers.
Uses of Diethyl carbamzine:
It is used to treat:-
1. Round worm
infestations
2. Filarial
infection
a) Ochocerciasis (river blindness)
b) Lymphatic
filariasis
3. Loiasis (infection due to Loa Loa)
4. Tropical eosinophilia
Pharmaceuticals formulations:-
1. Diethylcarbamazine
injection
2. Diethylcarbamazine
tablets
Brand Names:
1. Filazine
2. Hetrazen
3. Bonocide
forte.
Mebendazole
• It is benzimidazole derivatives and
contains methyl carbamate (-NHCOOCH3 group at C2 position and benzoyl group at
C5.
Physical
Properties of Mebendazole:
1. It is
white or slightly yellow powder,
2. It is practically insoluble in
water.
Stability
and storage of Mebendazole:-
• It is stable under normal condition of
temperature, light and moisture .it is stored in well closed containers.
Uses of Mebendazole:
it is broad spectrum Anthelmentics, it is used to treat.
1. Whipworm
infestation
2. Round worm infestation
3. Tape worm
infestation
4. Thread
worm infestation
5. River
blind ness.
6. Hookworm
infestation
7. Guinea
worm infestation
8. Capillaria
infestation
Pharmaceutical formulations:-
Mebendazole tablets
Brands names:
1. Mebex
2. Wormin
3. wormokil