2. INTRODUCTION
Helminth are multicellular worm with digestive, excretory, nervous, and
reproductive system.
HELMINTHIASIS is a disease in which a part of body is infested with one or more
intestinal parasitic worms such as round worm, tapeworms or fluckers.
The worms usually infest the intestine but sometimes, they may invade other
organs
3. HELMINTH CAN BE DIVIDED INTO 2 MAJOR CLASSES
HELMINTHS
Phylum
PLATYHELMINTHS
(FLAT WORMS)
CESTOIDEA TREMATODA
Phylum
NEMATHELMINTHS
(ROUND WORMS)
NEMATODA
7. Antihelminthic drugs
Benzimidazoles (BZ)
The discovery by Brown and co-workers that thiabendazole possessed potent
activity against GI nematodes.
Albendazole
Mebendazole
Thiabendazole
Triclabendazole
8. Mechanism of action Disturb the
formation of
microtubules
inside the
worm cell and
Transport
glucose
molecules in to
the cell by
endocytosis
polymerization
D
D
D
No microtubules inside worm
cell
Glucose molecule cannot be
transported inside the cell by
endocytosis
SELECTIVE FOR THE NEMATODAL
ISOFORM OF BETA TUBULIN
9. GENERAL ADVERSE EFFECT
General side effect:
Abdominal pain
Diarrhoea
Dizziness
Headache
Insomnia
Loss of appetite
Hypersensitivity
Vomiting
Granulocytopenia
Alopecia
Jaundice
Thiabendazole has
more adverse effect
compare to other BZ
Liver failure and
Stevens-Johnson
syndrome rarely
10. THERAPEUTIC USES
ALBENDAZOLE
• 400 mg single dose (adults)
Round worm
Ascaris lumbricoides
• 400 mg single dose (adults)
• 200 mg single dose (1-2 yrs)
Hook worm
Ancylostoma duodenale
Necator americanus
• 400 mg single dose (adults)
• 200 mg single dose (1-2 yrs)
Whip worm
Trichuris trichiura
As First Choice Of Drug
11. • 400 mg BD for 28 days with fatty
meals.
• Along with corticosteroid.
CYSTICERCOSIS
Taenia solium
• 400 mg BD for 28 days with fatty
meals.
HYDATID DISEASE
ECHINOCOCCOIS
• Caused by Hookworm
Cutaneous Larva Migrants
Visceral Larva Migrants
12. AS SECOND CHOICE DRUG
• Strongyloides Stercoralis
THREAD WORM
• +diethylcarbamazine or ivermectin
LYMPHATIC FILARIASIS
• Enterobius vernicularis
PIN WORM
13. MEBENDAZOLE
Therapeutic uses
• 100 mg BD for 3 days
Round worm
Hook worm
• 100 mg single dose repeat after 2 weeks
Pin worm
Trichinosis
14. VISCERAL LARVA MIGRANTS
TAENIA SAGINATA
Hydatid disease
Mebendazole is an alternative drug to metronidazole in guinea worm infection: also
preferred drug for multiple infections
15. PYRANTEL PAMOATE,OXANTEL PAMOATE
Introduced in 1969
PHARMACOKINETICS
Poor absorbed from GIT(10-15% of an oral dose).
Active against luminal helminth.
Excretion : <15% in urine as parent drug metabolites major
portion in feces.
16. Mechanism of action
Depolarizing Neuromuscular Blocking
Agent
Activation of nicotinic receptor of NMJ
Persistence depolarization
Contraction and spastic paralysis of worm
Loose their attachment to intestinal
lumen and expelled in feces
17. Adverse effect
Headache
Dizziness
Rash
Fever
Safety in pregnancy
Safety in children below 2 year not established
19. PIPERAZINE
Introduced in 1950
A secondary cyclic amine
PHARMACOKINETICS
Orally absorbed from GIT
Metabolized in liver
Excreted in urine
20. MECHANISM OF ACTION
Flaccid Paralysis Expels Alive Worms
Hyperpolarization & Relaxation Of Muscle
Activate GABA gated Cl- Channels in nematode muscle
GABA receptor Agonistic
21. ADVERSE EFFECT
General side effect
Toxic dose produce convulsion
death due to respiratory failure
Neurotoxic and allergic reaction rarely
Contraindication
In patient of epilepsy
In patient with impaired renal and hepatic functions
22. DIETHYLCARBAMAZINE
Developed in 1948
Synthetic piperazine derivative available as citrate salt
PHARMACOKINETICS
Rapidly absorbed
Distributed all over body except fat
Metabolized in liver
Excreted in urine as N-Oxide metabolite and extra urinary roots
Plasma half life 4-12 hrs
23. MECHANISM OF ACTION
Alter microfilarial membrane surface characteristics
Overstimulation of neuromuscular system of the parasite and
increased motility
Inhibits acetylcholinesterase production by parasites, es
lysosomal enzymes β-glucuronidase and acid phosphatase that
are involved in phagocytosis
induce nitric oxide which is essential for the rapid sequestration
of microfilariae by diethylcarbamazine citrate
24. THERAPEUTIC USES
• 2mg/kg TDS is a first line drug
• patient becomes noninfective to mosquitoes in 7
days
• 12 days to 3 weeks treatment for radical cure
LYMPHATIC FILARIASIS
• 300 mg weekly
LOASIS
• 2 mg/kg orally TDS for 7 days
TROPICAL EOSINOPHILIA
25.
26. ADVERSE EFFECT
TWO TYPE
1] Pharmacological dose depended
Headache
Malaise
2] Allergic reaction to dying filarial parasite
Rash, Pruritus
Enlargement of lymph nodes,
Bronchospasm
Fall in BP
30. THERAPEUTIC USES
DRUG OF CHOICE
• River blindness
ONCHOCERCIASIS
• Higher cure rate
DISSEMINATED STRONGYLOIDIASIS
• 200 mcg/kg single dose
Pediculosis (lice infestation) and Scabies
31. • Single annual dose with 400 mg albendazole for 5-6 yrs
LYMPHATIC FILARIASIS
32. PRAZIQUANTEL
Synthetic isoquinoline-pyrazine derivative.
PHARMACOKINETICS
Well absorbed (80%)
Metabolized in liver
Plasma half life 1-3 hrs
Crosses blood brain barrier
Excreted as metabolite in urine
33. MECHANISM OF ACTION
spasms and paralysis of the worms' muscles by a rapid
Ca 2+ influx inside the schistosome by acting on voltage gated
ca++ channels.
34. ADVERSE EFFECTS
GENERAL SIDE EFFECTS
CONTRAINDICATION
Ocular cysticercosis because of the risk of severs eye damage resulting from
occlusion due to dead parasites.
PREGNANCY
CHILDREN BELOW 5 YRS
35. THERAPEUTIC USE
• 20 mg/kg BD
SCHISTOSOMIASIS
• 20 mg/kg TDS
S. JAPONICUM
• 10 mg/kg single dose in morning
T.SOLIUM, T SAGINATA
36. • 50 mg/kg divided in 3 dose for 15 days
NEUROCYSTOCERCOSIS
• 75 mg/kg OD for 1 or 2 days
FOR OTHER FLUKES
Except F. hepatica
• 15-25 mg/kg single dose in morning
D.LATUM, H.NANA
Phagocytosis is a process by which a cell can transport substances across the cytoplasmic membrane and into the cytoplasm. Cells that are capable of phagocytosis are collectively known as phagocytes and include neutrophils, eosinophils, and macrophages. Phagocytosis is part of the body's second line of defense, and it is nonspecific. It includes the following steps:Chemotaxis: A cell moves either toward or away from a chemical stimulus.Adherence: The phagocyte attaches to the pathogen, through binding of complementary chemicals on the membranes of the pathogen.Ingestion: After the pseudopodia adhere to the pathogen, the encompassed microbe is internalized as the pseudopodia fuse to form a sac called a phagosome.Digestion: Lysosomes with over 30 digestive enzymes attach to the phagosome and break down the microbe. At the end of this process, the remains of the phagosome are known as the residual body.Elimination: The phagocyte rids itself of undigested material by exocytosis, which is the opposite of ingestio