Mode of action of anthlemintics

2. Mode of Action of
Anthelmintics
Usman Khalid
Roll No.27

3. Groups of Anthelmintics
• Benzimidazole
• Avermectin
• Imidazothiazole
• Tatrahydrophyrimidines
• Peperozine
• Organophasphates
• Isoquinoles
• Arsenicals

4. Benzimidazole

5. Members
• Albendazole
• Fenbendazole
• Flubendazole
• Mebendazole
• Febantel
• Oxfendazole
• Oxibendazole
• Triclabendazole
• Sulfoxide
• Thiabendazole
• Thiophanate
• Netobimin

6. In Low concentration

7. Binds to
Tubulin
Prevent
polymerization
Microtubule
s Disrupted
Cellular
transport
effected
Cellular
process
Glycogen
utilized
Mitochondria
and RE
functionality
ATP
Cessation
and so
death

8. In High Concentration

9. Inhibits Malate
dehydrogenase
and fumarate
reductase
Metabolic
pathway
Disturbed
Death

10. Avermectin

11. Members
• Ivermectin
• Abamectin
• Doramectin
• Eprinomectin
• Selamectin
• Moxidectin

12. •Paralysis of the somatic worm musculature
•Inhibit feeding of the parasite by blocking
pharyngeal pumping.
•Disruption of ingestive activity and worm
starvation.

13. Act on
GABBA
Enhance its
Release
Act as inhibitory
neurotransmitter
Block post-
synaptic
stimulation
Paralysis and
death

14. Imidazothiazole

15. Members
• Levamisole

16. Why they are effective for only Parasites???
• Acetylcholine agonists
• The surface of somatic muscle cells of nematodes possess nicotinic
acetylcholine receptors (nAChR) that can be opened by the nicotinic
anthelmintics
• Selective toxicity of these compounds appears to be based on the
unique properties of the nematode nAChR
• They lack subunit lacks the conserved target amino acid residue for
lophotoxin present in all muscle and neuronal AChRs of other
invertebrates and vertebrates.

18. In Low concentration

19. Act on
CNS
Stimulate para-
sympahtic and
sympahtic gangliaParalysis
Death

20. In High Concentration

21. Act on
Carbohydrate
metabolism
Fumarate
reduction
Succinate
oxidation
Paralysis
Expelled
out of
body as
such

22. Act on Immune
system
Cell mediated
immunity
restored in T-
Cells
Phagocytosis
increased by
monocytes

23. Isoquinoles

24. Members
• Praziquantel
• Epsiprantel

25. •Pyrazino-isoquinoline ring system of
praziquantel represents a completely novel
structure in anthelmintic therapy with no
relationship to other antiparasitic drug
structures.
•The drug causes an immediate muscle
contraction and vacuolisation of the tegument.

26. In Low concentration

27. Act on
integuments
Ions fluxes
occur of
Na,Ca,K
Impairs
function of
suckers
Stimulate
worm
motility
Death

28. In High Concentration

29. Increase
contraction
of worm
strobilla
Death

30. Tatrahydrophyrimidines

31. Members
• Pyrantel

32. Act on CNS
Neurotransmitter
blocking agent also
blocks
Cholinestrase
paralysis
Death