8.ANTHELMINTIC DRUGS

BYBY

Dr. Dr. SAMINATHAN KAYAROHANAMSAMINATHAN KAYAROHANAM

M.PHARM, M.B.A, PhDM.PHARM, M.B.A, PhD

ANTHELMINTIC DRUGS

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NUM CONTENT SLIDE

1 OVERVIEW TO ANTHELMINTIC 4-12

2 NEMATODE (ROUND WORMS) 13-36

3 TERMATODES ( FLUKES ) 37-52

4 CESTODES ( TAPEWORMS) 53-67

5 RELATIVE INCIDENCE OF HELMINTH INFECTIONS WORLDWIDE

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6 ANTHELMINTIC DRUGS 69-78

7 CHEMICAL STRUCTURES OF ANTHELMINTIC DRUGS

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8 CLINICAL USE OF ANTHELMINTIC DRUGS 80

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LEARNING OUTCOME

1. Describe and understand the infectious diseases of Helminthiases and life cycles.

2. Morphology, Scientific classification and symptom of

NEMATODE (ROUND WORMS), TERMATODES ( FLUKES ) and CESTODES ( TAPEWORMS).

3. Able to list the classification of anthelmintic drugs.

4. Abele to demonstrate the general mechanism of anthelmintic drugs.

5. Able to understand the anthelmintic drugs available drugs in the market.

Predator. “An organism that eats more than one other organism (animal) during its life.” Usually larger than prey (exception: social predators).

Parasite. “An organism that lives at the expense of another (host), which it does not usually kill.” Usually smaller than host.Parasitoid. “A parasite that kills its host.” Usually smaller than host.

Cleptoparasite. ‘A “thief” parasite, one that consumes the food stored by another insect in a nest. (Evans, 1984) Smaller or similar size as host; often closely related.

Hyperparasite. Parasite of a parasite. Usually smaller than host.4

1. OVERVIEW TO ANTHELMINTIC

4Dr.K.Saminathan.M.Pharm, M.B.A, Ph.D

Parasites are usually much smaller than their hosts, they also do not kill before they eat.5


5 Dr.K.Saminathan.M.Pharm, M.B.A, Ph.D

INTRODUCTION TO AMOEBA

Entamoeba histolyticaAmoebic dysentery

Naegleriaprimary amoebic

meningoencephalitisAcanthamoeba

contact lens contaminant

6 Figure 12.18a

• Protozoa with no truly defined shape • Move and acquire food through the use of

pseudopodia• Found in water sources throughout the

world• Few cause disease



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1. OVERVIEW TO ANTHELMINTICThe helminths comprise two major groups of multicellular worms that evolved from a common ancestor some 600 million years ago and diverged into two rather different groups.

The nemathelminths (nematodes, roundworms) and the platyhelminths (flatworms).

The latter group is subdivided into the trematodes (flukes) and the cestodes (tapeworms).

Almost 350 species of helminths have been found in humans, and most colonise the gastrointestinal tract.

Helminths have a complex life cyclecomplex life cycle, often involving several species. Infection by helminths may occur in many ways, and poor hygiene is a major contributory factor.

ConDr.K.Saminathan.M.Pharm, M.B.A, Ph.D

Many enter by mouth in unpurified drinking water or in badly cooked meat from infected animals or fish. However, other types can enter through the skin following a cut, an insect bite or even after swimming or walking on infected soil.

Humans are generally the primary (or definitive) host for helminth infections, in the sense that they harbour the sexually mature form that reproduces.

Eggs or larvae then pass out of the body and infect the secondary Eggs or larvae then pass out of the body and infect the secondary (intermediate) host. In some cases, the eggs or larvae may persist in (intermediate) host. In some cases, the eggs or larvae may persist in the human host and become the human host and become encystedencysted, covered with granulation , covered with granulation tissue, giving rise to tissue, giving rise to cysticercosiscysticercosis. This is characterised by encysted . This is characterised by encysted larvae in the muscles and the viscera or, more seriously, in the eye or larvae in the muscles and the viscera or, more seriously, in the eye or the brainthe brain.

Approximately 20 helminth species are considered to be clinically significant, and these fall into two main categories-those in which the worm lives in the host's alimentary canal, and those in which the worm lives in other tissues of the host's body 8


Dr.K.Saminathan.M.Pharm, M.B.A, Ph.D

CLASSIFICATION OF HELMINTHES: THEY ARE TWO PHYLA CLASS: NEMATODES (ROUND WORMS)

I) Intestinal Nematodes: 1) Round worms as Ascaris. 2) Hookworms as Ancylostoma. 3) Pinworms as Oxyuris. 4) Whipworms as Trichuris. 5) Thread worms as Strongyloids. 6) Enterobius Vermicularis.

II) Tissue Nematodes:Filaria.

Phylum: Platyhelminthes ( flatworms)

CLASS: TERMATODES ( FLUKES )

1) Liver flukes: Fasciola Hepatica. Fasciola Gigantica

2) Blood flukes: Schistosoma haematobium. Schistosoma mansoni.

3) Intestinal flukes: Heterophyes heterophyes.

CLASS: CESTODES ( TAPEWORMS )

Beef tapeworm:Taenia saginata.

Pork tapeworm:Taenia solium.

Dwarf tapeworm:Hymenolepis nana.9



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INFECTIOUS DISEASES - HELMINTHIASES


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INFECTIOUS DISEASES - HELMINTHIASES


The nematodes or roundworms constitute the phylum Nematoda. Nematode species can be difficult to distinguish, and although over 25,000 25,000 have been described, of which more than half are parasitic.

total number of nematode species has been estimated to be about 1 million.

Nematodes have tubular digestive systems with openings at both ends.

The fertilized female can lay about 200,000 eggs per day.200,000 eggs per day. Eggs require oxygen and moisture to embryona

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NEMATODES (ROUND WORMS)


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Nematodes comprise the group of organisms containing the largest number of helminth parasites of humans.

Range in size, many are very small few millimeters but some may be up to a meter in length.

“Largest Nematode measured 9 meters long and 2.5 cm in diameter, found as parasite in a Sperm Whale’s placenta”.They are unsegmented, bilaterally symmetrical, and exhibit great variation in their life cycles. Generally, they are long-lived (1-30+ years).

some can have both free-living and parasitic stages in their life cycle.

Adult Looks like an earthwormFemale (20-35 cm); Male (12-30 cm)3 lips which carry minute teeth

2. NEMATODE (ROUND WORMS)


2. NEMATODE ( ROUND WORMS) THE INTESTINAL

NEMATODES2.1. Ascaris2.2 Hook worms2.3 Pin worm2.4 Whip worm

THE BLOOD- AND TISSUE DWELLING NEMATODES2.5 The filaria2.6 Trichinella

The larvae initially burrow into the mucosa, penetrate blood vessels and appear as second stage larvae in the liver within six hours post-infection.

Here they remain for several days and develop into third stage larvae, L3. These larvae then migrate to the heart and are carried to the lungs via the pulmonary arteries, arriving within four to seven days.

From there they break out of the capillaries into the alveoli and finally work their way up the trachea to the pharynx and reach the small intestine on the 8th or 10th day post-infection.


Most diagnoses are made by identifying the appearance of the worm or eggs in feces.

Due to the large quantity of eggs laid, physicians can diagnose using only one or two fecal smears.

Infections can be treated with drugs called ascaricides. The treatment of choice is MEBENDAZOLE. The drug functions by binding to tubulin in the worms' intestinal cells and body-wall muscles. Nitazoxanide and ivermectin can also be used

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2.1 ASCARIS(Ascaris lumbricoides)






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2.1 ASCARIS lumbricoides is the giant roundworm of humans, growing to a length of up to 35 cm. It is one of several species of Ascaris. An ascarid nematode of the phylum Nematoda, it is the largest and most common

parasitic worm in humans.


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The most common treatment for hookworm is benzimidazoles,

specifically ALBENDAZOLE and MEBENDAZOLE

2.2 HOOK WORMS

Hookworm is a parasitic nematode that lives in the small intestine of its host, which may be

a mammal such as a dog, cat, or human. Three species of hookworms commonly infect

humans:


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2.2 HOOK WORMS


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Ancylostoma duodenale, Necator americanus and Strongyloides

stercoralis. A.

2.2 HOOK WORMS LIFE CYCLE


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Strongyloidiasis is a human parasitic disease caused by the nematode (roundworm) called Strongyloides stercoralis, or sometimesS. fülleborni which is a type of helminth.

It belongs to a group of nematodes called hookworms. This intestinal worm can cause a number of symptoms in people, principally skin symptoms, abdominal pain, diarrhea and weight loss.

The diagnosis is made by blood and stool tests. The drug IVERMECTIN is widely used in the treatment of strongyloidiasis

2.3 STRONGYLOIDIASIS

Frequently asymptomatic. Gastrointestinal system symptoms include abdominal pain and diarrhea. Pulmonarysymptoms (including Löffler's syndrome) can occur during pulmonary

migration of the filariform larvae.


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2.3 STRONGYLOIDIASIS


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The pinworm (genus Enterobius), also known as threadworm (in the United Kingdom and Australia) or seatworm, is a parasitic worm.

It is a nematode(roundworm) and a common intestinal parasite or helminth, especially in humans. The medical condition associated with pinworm infestation is known as enterobiasis (a type of helminthiasis).

THE CHIEF SYMPTOM IS ITCHING IN THE ANALAREA.

ALBENDAZOLE or MEBENDAZOLE is the first-line treatment of pinworm infection.

PYRANTEL PAMOATE is alternative.

2.4. PIN WORM


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2.4. PIN WORM


The pinworm (genus EnterobiusEnterobius), also known as threadworm (in the United Kingdom and Australia) or seatworm, is a parasitic worm.

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2.4. PIN WORM LIFE CYCLE


The human whipworm (Trichuris trichiura or Trichocephalus trichiuris) is a round worm (a type of helminth) that causes

trichuriasis (a type of helminthiasiswhich is one of the neglected tropical diseases) when it infects a

human large intestine.

It is commonly known as the whipworm which refers to the shape of the worm; it looks like a whip with

wider "handles" at the posterior end.

SymptomsBloody diarrheaIron-deficiency anemiaFecal incontinence (during sleep)Rectal prolapse

TreatmentMEBENDAZOLE taken by mouth for 3 days is

commonly prescribed when the infection causes symptoms. ALBENDAZOLE OR

IVERMECTIN may sometimes be used.

2.5. WHIP WORM


2.5. WHIP WORM


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2.5. WHIP WORM

(TRICHIURA) LIFE CYCLE


The Filarioidea are a superfamily of nematodes (roundworms).The members of this superfamily are known as filarial worms. Infections with parasitic filarial worms cause filariasis.

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People with the disease can suffer from lymphedema and elephantiasis and in men, swelling of the scrotum, called hydrocele. Lymphatic filariasis is a leading cause

of permanent disability worldwide.

2.6. FILARIA

standard-dose ALBENDAZOLE-IVERMECTIN

treatment

SurgeryLymphatic filariasis


2.7. FILARIA


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2.5. FILARIA LIFE CYCLE


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SYMPTOMSDiarrheaAbdominal crampsTirednessMuscle aches and painsHigh feverSwelling in your eyes and faceEye infection (conjunctivitis, or pink eye)Rashes

Trichinosis or trichiniasis, is a parasitic disease caused by eating raw or undercooked pork or wild game infected with the larvae of a species of roundworm Trichinella spiralis, commonly

called the trichina worm. There are eight Trichinella species

PRIMARY TREATMENT

Early administration of anthelmintics, such as

MEBENDAZOLE or ALBENDAZOLE,

Secondary treatmentAfter infection, steroids, such as prednisone may be used to relieve muscle pain associated

with larval migration.

2.8. TRICHINELLA


2.8. TRICHINELLA


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2.8. TRICHINELLA LIFE CYCLE


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THERAPY FOR NEMATODE INFECTIONS


The trematodes (or flukes) are leaf shaped with an outer cover called the tegument which may be smooth or spiny. There are two suckers or attachment organs, an anterior oral sucker and a posterior ventral sucker. The suckers form a characteristic feature of the group, from which the name Trematode is derived from the Greek word Trematode is derived from the Greek word for “holefor “hole.” They can occur in a variety of host environments, with the majority being endoparasites but some are found to be ectoparasitic.Most trematodes are hermaphroditic and most of the body consists of reproductive organs and their associated structures. The digestive system is well developed; they generally feed on intestinal debris, blood, mucus and other tissues, depending on the host environment.

3. TERMATODES ( FLUKES )


Fasciolosis the common liver fluke) and Fasciola gigantica.

Both species overlap in many areas of Africa and Asia.

host range is very broad and including humans.

life cycle includesfreshwater snails as an intermediate host of the parasite.

Recently, worldwide losses in animal productivity due to fasciolosis were conservatively estimated at over US$3.2 billion per annum.

In addition, fasciolosis is now recognized as an emerging human disease: the World Health Organization (WHO) has estimated that 2.4 million people are infected with Fasciola, and a further 180 million are at risk of infection. 38

3.1. FASCIOLA


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The Liver Fluke Infection: FascioliasisThe Liver Fluke Infection: Fascioliasis

Adult fluke of a Fasciola Trematode. Their morphology shows a large

leaf-shape about 2–3cm long with two suckers, an oral and

a ventral one.

3.1. FASCIOLA SPECIES


GEOGRAPHIC DISTRIBUTION

RESERVOIR HOSTS

HOSTLOCATION

OF ADULT IN SIZE OF OVA

Fasciola hepatica

Cosmopolitan Sheep Bile Ducts130-150µm by

63-90µm

Fasciola gigantica

Africa, the Orient and Hawaiian Islands

Camels, Cattle and

Water BuffaloBile Ducts

160–190µm by 70-90µm

Fasciolopsis buski

Far-East and Indian Sub-continent

Pigs, Dogs and Rabbits

HumanIntestine

130–140µm by 80-85µm

Echinostoma species

South East Asia and Japan

Variety of Mammals

Intestine88–116µm by

58-69µm40

3.1. FASCIOLA SPECIES


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3.1. FASCIOLA SPECIESTRICLABENDAZOLE (Egaten) in dose 10–12 mg/kg is the drug of

choice in human fasciolosis. PRAZIQUANTEL treatment is ineffective.


3.2. CLONORCHIS SINENSISClonorchis sinensis, also known as the Chinese (aka Oriental) liver fluke is a narrow elongate liver fluke found in the Far East, mainly Japan, Korea, China, Taiwan and Vietnam.Three main species which commonly infect man. All members of this group are parasites of fish-eating mammals, particularly in Asia and Europe. Man is the definitive hosts and water snails and fish are the intermediate hosts.Infections can be easily avoided by man not eating raw fish since this is the only way that infection can be passed on.Clonorchis sinensis parasitize the biliary duct in humans who become infected by eating raw or undercooked fish. Dogs and cats are the most important reservoir hosts.

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Drugs used to treat infestation include triclabendazole,praziquantel, bithionol, albendazole, levamisole and

mebendazole.However, benzimidazoles are very weak as vermicide. PRAZIQUANTEL is the drug of choice.


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3.2. CLONORCHIS SINENSIS LIFE CYCLE


3.2. CLONORCHIS SINENSIS


Heterophyes heterophyes

Metagonimus yokogawai

Opisthorchis viverrini

Dicrocoelium dendriticum

Geographic distribution

Far East Far East Thailand Far East

Location of adult in host

Small intestine Small intestineLiver and bile

ductsLiver and bile

ducts

Size of ova26.5-30mm

by15-17mm

26.5-30mm by

15-17mm

26.7mm by

15mm

38-45mm by

22-30mm

Shape of ovaProminent opercular

shoulders Bile stained

Prominent opercular


Prominent opercular


Dark brown, thick shelled

and large operculum

Infection acquired by

Eating raw or pickled fish

Eating raw or pickled fish

Eating raw fresh water fish

Eating infected ants

SymptomsOccasionally diarrhea

and vomiting

Occasionally diarrhea and

vomiting

Malaise and right upper

quadrant pain

Biliary and digestive

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3.2. LESS COMMON FLUKES THAT ARE KNOWN TO INFECT MAN


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3.2. PARAGONIMUS WESTERMANIParagonimus westermani is a lung fluke found in both humans and animals. The adults are 12µm long and are found in capsules in the lung. The species

sometimes is called the Japanese Lung fluke or Oriental Lung fluke. Human infections are most common in eastern Asia and in South America.

The symptoms bad cough, bronchitis, and blood in sputum (hemoptysis)

PRAZIQUANTEL is the drug of choice to treat paragonimiasis.The recommended dosage of 75 mg/kg per day, divided into 3 doses over 3 days has proven to eliminate P. westermani


3.3. PARAGONIMUS WESTERMANI


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The Schistosomes are blood trematodes

They are the only trematodes that live in the blood stream of warm-blooded hosts.

Over 200 million people are infected over at least 75 countries with 500 million or more people exposed to infection.

With the disease spreading due to improved water supplies.

3.4. SCHISTOSOMA

Schistosomiasis is treatable using a single dose of the drug

PRAZIQUANTEL by mouth annually


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3.4. SCHISTOSOMA


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3.4. SCHISTOSOMA


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3.4. SCHISTOSOMA


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3.5 THERAPY FOR TREMATODE INFECTIONS


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Cestoda (cestoidea) is the name given to a class of parasitic flatworms,

The best-known species are commonly called tapeworms. Cestodes are all parasitic and their life histories vary, but typically they live in the digestive tracts of vertebrates as adults, and often in the bodies of other species of animals as juveniles.

Humans are subject to parasitism by several species of tapeworms if they eat undercooked meat such as pork (taenia solium), beef (t. Saginata), and fish (diphyllobothrium spp.), Or if they live in, or eat food prepared in, conditions of poor hygiene (hymenolepis orechinococcus species).

T. Saginata, the beef tapeworm, can grow up to 20 m (65 ft); the largest species, the whale tapeworm polygonoporus giganticus, can grow to over 30 m (100 ft).

Discovered in fossil feces (coprolites) of a shark dating to the mid- to late permian, some 270 million years ago.

4. CESTODES ( TAPEWORMS)


4. CESTODESTaenia saginata Taenia solium

35 mm. Range, 31-43 mm.

Walnut brown. Thick, striated shell. Eggs of T. solium and T. saginata are indistinguishable and species identification should be made from proglottids or scoleces. "Taenia" spp. should be reported if only eggs are found.

Hymenolepis nana 47 mm x 37 mm. Range, 40-60 mm x 30-

50 mm.

Colorless, almost transparent.

Polar filaments.

Hymenolepis diminuta*

72 mm. Range, 70-86 mm x 60-80 mm.

Yellow. Resembles H. nana but lacks polar filaments. Poles are rudimentary and often hard to see.

Dipylidium caninum*

35-40 mm. Range, 31-50 mm x 27-48mm.

Colorless. Eggs are contained in a sac or capsule which ranges in size from 58mm to 60 mm x 170 mm. Occasionally capsules are ruptured and eggs are free.

Diphyllobothrium latum

66 mm x 44 mm. Range, 58-76 mm x 40-

51 mm.

Yellow to brown. Egg resembles hookworm egg but has a thicker shell and an operculum


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Taenia saginata commonly known as the beef tapeworm, It is an intestinal parasite of cattle and humans, causing taeniasis (a type ofhelminthiasis) in humans.

It is found globally and most prevalently where cattle are raised and beef is consumed. It is relatively common in Africa, some parts of Eastern Europe, Southeast Asia, South Asia, and Latin America.

Humans are generally infected as a result of poor hygiene.

It is typically larger and longer

4.1. TAENIA SAGINATA


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4.1. TAENIA TAPEWORMS IN HUMANS


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SYMPTOMST. saginata infection is usually asymptomatic, but

heavy infection often results in weight loss, dizziness, abdominal pain, diarrhea, headaches,

nausea, constipation, chronic indigestion, and loss of appetite.

TREATMENTTaenaisis is easily treated with PRAZIQUANTEL (5–10 mg/kg, single-administration) or NICLOSAMIDE

(adults and children over 6 years: 2 g) ALBENDAZOLE is also highly effective for treatment of cattle infection



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4.1. TAENIA SAGINATA LIFE CYCLE


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4.2. HYMENOLEPIS NANADwarf tapeworm is one of the most common cestodes (a type of intestinal worm or helminth) infecting humans, especially children.

Hymenolepiasis is infestation by one of two species of tapeworm: Hymenolepis nana or Hymenolepis diminuta.

The 2 drugs that have been described for the treatment of

hymenolepiasis are PRAZIQUANTEL and

NICLOSAMIDE.

ABDOMINAL DISCOMFORTDEHYDRATION FROM PROLONGED

DIARRHEA


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4.2. HYMENOLEPIS NANA


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4.2. HYMENOLEPIS NANA


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Diphyllobothrium is a genus of tapeworm which can cause Diphyllobothriasis in humans through consumption of raw or undercooked fish.

That infects fish and mammals. D. latum is native to Scandinavia, western Russia, and North America,. East Russia.

The salmon tapeworm which has a much larger range

The standard treatment for diphyllobothriasis, as well as many other tapeworm infections is a single dose of PRAZIQUANTEL, 5–10 mg/kg PO once for both adults and children. An alternative treatment is NICLOSAMIDE, 2 g PO once for adults or 50 mg/kg PO once.

4.3. DIPHYLLOBOTHRIUM



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THERAPY FOR CESTODE INFECTIONS


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5. RELATIVE INCIDENCE OF HELMINTH INFECTIONS WORLDWIDE


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6. ANTHELMINTIC DRUGS

roundworms

(flukes) are leaf-shaped flatworms

tapeworms


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Diethylcarbamazine is used in the treatment of filariasis because of its ability to immobilize microfilariae and render them susceptible to host defense mechanisms.

Combined with albendazole, diethylcarbamazine is effective in the treatment of Wuchereria bancrofti and Brugia malayi infections.

It is rapidly absorbed following oral administration with meals and is excreted primarily in urine.

Symptoms include fever, malaise, rash, myalgias, arthralgias, and headache, and their severity is related to parasite load.

Most patients have leukocytosis. Antihistamines or steroids may be given to ameliorate many of the symptoms.

6.1. DIETHYLCARBAMAZINE


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Ivermectin is the drug of choice for the treatment of onchocerciasis (river blindness) caused by Onchocerca volvulus and for cutaneous larva migrans and strongyloidiasis.

Ivermectin targets the parasite’s glutamate-gated chloride channel receptors. Chloride influx is enhanced,

and hyperpolarization occurs, resulting in paralysis of the worm.

The drug is given orally. It does not cross the blood-brain barrier and has no pharmacologic effects in the CNS.

Ivermectin is also contraindicated in pregnancy.The killing of the microfilaria can result in a Mazotti-like reaction (fever, headache, dizziness, somnolence, and hypotension).

6.2. IVERMECTIN


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Mebendazole a synthetic benzimidazole compound, is effective against a wide spectrum of nematodes.

It is a drug of choice in the treatment of infections by whipworm (Trichuris trichiura), pinworm (Enterobius vermicularis), hookworms (Necator americanus and Ancylostoma duodenale), and roundworm (Ascariasis lumbricoides).

Mebendazole acts by binding to and interfering with the assembly of the parasites' microtubules and also by decreasing glucose uptake. Affected parasites are

expelled with the feces.

Mebendazole is relatively free of toxic effects, although patients may complain of abdominal pain and diarrhea. It is, however, contraindicated in pregnant women ,because it has been shown to be embryotoxic and teratogenic in experimental animals.

6.3. MEBENDAZOLE


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Pyrantel pamoate along with mebendazole, is effective in the treatment of infections caused by roundworms, pinworms, and hookworms. Pyrantel pamoate is poorly absorbed orally and exerts its effects in the intestinal tract.

It acts asa depolarizing, neuromuscular-blocking agent, causing persistent activation of

the parasite’s nicotinic receptors.

The paralyzed worm is then expelled from the host’s intestinal tract. Adverse effects are mild and include nausea, vomiting, and diarrhea.

6.4. PYRANTEL PAMOATE


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Thiabendazole another synthetic benzimidazole,is effective against strongyloidiasis caused by Strongyloides stercoralis (threadworm), cutaneous larva migrans, and early stages of trichinosis (caused by Trichinella spiralis;

Thiabendazole, like the other benzimidazoles, affects microtubular aggregation.

Although nearly insoluble in water, the drug is readily absorbed on oral administration.

It is hydroxylated in the liver and excreted in urine. The adverse effects most often encountered are dizziness, anorexia, nausea, and vomiting. There have been reports of central nervous system (CNS) symptomatology.

There have been a number of fatalities among thecases of erythema multiforme and Stevens-Johnson syndrome reportedly caused by thiabendazole. Its use is contraindicated during pregnancy.

6.5. THIABENDAZOLE


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Trematode infections are generally treated with praziquantel. This drug is an agent of choice for the treatment of all forms of schistosomiasis and other trematode infections and for cestode infections like cysticercosis.

Permeability of the cell membrane to calcium is increased, causing contracture and paralysis of the parasite.

Praziquantel is rapidly absorbed after oral administration and distributes into the cerebrospinal fluid. High levels occur in bile. The drug is extensively metabolized oxidatively, resulting in a short half-life.

Common adverse eff ects include drowsiness, dizziness, malaise, and anorexia as well as gastrointestinal upsets. The drug is not recommended for pregnant women or nursing mothers. Drug interactions due to increased metabolism have been reported .

Praziquantel is contraindicated for the treatment of ocular cysticercosis, because destruction of the organismin the eye may damage the organ.

6.6. PRAZIQUANTEL


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Broad spectrum Drug of choice for treatment of hydatid

disease and cysticercosis. Used for the treatment of ( intestinal nematodes )

e.g. ascariasis , tricurasis and strongyloidiasis, pinworm, hookworm

Inhibits microtubule synthesis that irreversibly impairs glucose uptake ,

intestinal parasites are immobilized and die slowly.

larvicidal in : hydatid ,cysticercosis , ascariasis and hook worm infections.

Ovicidal in ascariasis ,hookworm , trichuriasis

6.7. ALBENDAZOLE


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Its primary therapeutic application, however, is in the treatment ofcestodal infestations, such as cysticercosis (caused by Taenia soliumlarvae) and hydatid disease (caused by Echinococcus granulosus).

Albendazole is erratically absorbed after oral administration, but absorption is enhanced by a high-fat meal.

Albendazole and its metabolites are primarily excreted in urine.

adverse effects are mild and transient and include headache and nausea. Parasites in the CNS, including headache, vomiting, hyperthermia, convulsions, and mental changes.

The drug should not be given during Pregnancy or to children under 2 years of age.

6.7. ALBENDAZOLE


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Niclosamide is the drug of choice for most cestode (tapeworm) infections.

Its action has been ascribed to inhibition of the parasite’s mitochondrial phosphorylation of

adenosine diphosphate, which produces usable energy in the form of adenosine triphosphate. anaerobic metabolism may also be inhibited.

Alcohol should be avoided within 1 day of niclosamide.

6.8. NICLOSAMIDE


7. CHEMICAL STRUCTURES OF ANTHELMINTIC DRUGS


8.CLINICAL USE OF ANTHELMINTIC DRUGS



Health & Medicine

8.ANTHELMINTIC DRUGS