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Albendazole is a broad-spectrum antihelmintic and antiprotozoal agent of the benzimidazole type.<ref name=AHFS2015/> It is used for the treatment of a variety of intestinal parasite infections, including ascariasis, pinworm infection, hookworm infection, trichuriasis, strongyloidiasis, taeniasis, clonorchiasis, opisthorchiasis, cutaneous larva migrans, giardiasis, and gnathostomiasis, among other diseases.<ref name=AHFS2015>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

Common side effects include nausea, abdominal pain, and headache.<ref name=AHFS2015/> Rare but potentially serious side effects include bone marrow suppression which usually improves on discontinuing the medication. Liver inflammation has been reported and those with prior liver problems are at greater risk.<ref name=AHFS2015/> It is pregnancy category D in Australia, meaning it may cause harm if taken by pregnant women.<ref name=AHFS2015/><ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

Albendazole was developed in 1975. <ref>Template:Cite book</ref> It is on the World Health Organization's List of Essential Medicines.<ref name="WHO23rd">Template:Cite book</ref> Albendazole is available in a fixed-dose combination with ivermectin.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

Medical usesEdit

Albendazole is an effective treatment for:

|CitationClass=web }}</ref>

|CitationClass=web }}</ref>

|CitationClass=web }}</ref> (especially neurocysticercosis), which is caused by the larval form of the pork tapeworm<ref name=AHFS2015 /> (i.e. albendazole is the drug of choice for larval pork tapeworms, but not adult pork tapeworms).<ref name=tripathi /> Old cysts are not affected.<ref name=yaffe-aranda />

      • Echinococcosis<ref name="who_mpi_1"/><ref name="pmid12667231">Template:Cite journal</ref> of the liver, lung, and peritoneum (caused by the larval form of the dog tapeworm, or of the alveoli (caused by E. multilocularis) when surgical excision is not possible.<ref name=AHFS2015 /> Alveolar and cystic echinococcosis may require lifelong treatment with albendazole, which only prevents the parasites from growing and reproducing rather than killing them.<ref name=turner-horton>Template:Cite book</ref>
  • Nematodes

|CitationClass=web }}</ref>

|CitationClass=web }}</ref>

|CitationClass=web }}</ref>

    • Ascariasis, which can be cured with a single dose of albendazole.<ref name="who_mpi_2">{{#invoke:citation/CS1|citation

|CitationClass=web }}</ref><ref name=sweet-gibbs>Template:Cite book</ref>

    • Baylisascariasis, caused by the raccoon roundworm. Albendazole can achieve good results (95–100% efficacy after a 10-day course of treatment) if treatment is initiated within 72 hours of ingestion of the egg-containing raccoon feces.<ref>{{#invoke:citation/CS1|citation

|CitationClass=web }}</ref>Template:Unreliable medical source Corticosteroids are sometimes added in cases of eye and CNS infections.<ref name=AHFS2015 />

    • Pinworm infection<ref name="who_mpi_2"/>
    • Filariasis; since albendazole's disintegration of the microfilariae ("pre-larva") can cause an allergic reaction, antihistamines or corticosteroids are sometimes added to treatment. In cases of lymphatic filariasis (elephantiasis) caused by Wuchereria bancrofti or Brugia malayi, albendazole is sometimes given as an adjunct to ivermectin or diethylcarbamazine in order to suppress microfilaremia. It can also be given for Loa loa filariasis as an adjunct or replacement to diethylcarbamazine.<ref name=AHFS2015 /><ref name=yaffe-aranda /> Albendazole has an embryotoxic effect on Loa loa adults and thus slowly reduces microfilaremia.<ref name=sweet-gibbs />
    • Gnathostomiasis when caused by Gnathostoma spinigerum.<ref name=AHFS2015 /> Albendazole has a similar effectiveness to ivermectin in these cases, though it needs to be given for 21 days rather than the 2 days needed for ivermectin.<ref name=turner-horton />
    • Gongylonemiasis<ref name=AHFS2015 />
    • Hepatic capillariasis caused by Capillaria hepatica<ref name=Sawamura>Template:Cite journal</ref>
    • Hookworm infections,<ref name="who_mpi_2"/> including cutaneous larva migrans caused by hookworms of genus Ancylostoma. A single dose of albendazole is sufficient to treat intestinal infestations by A. duodenale or Necator americanus.<ref name=AHFS2015 /><ref name=sweet-gibbs />
    • Intestinal capillariasis,<ref name="who_mpi_2"/> as an alternative to mebendazole<ref name=AHFS2015 />
    • Mansonelliasis when caused by Mansonella perstans. Albendazole is effective against adult worms but not against the immature microfilariae.<ref name=turner-horton />
    • Oesophagostomumiasis, when caused by Oesophagostomum bifurcum<ref name=AHFS2015 />
    • Strongyloidiasis,<ref name="who_mpi_2" /> as an alternative to ivermectin or thiabendazole.<ref name=AHFS2015 /><ref name=gouma>Template:Cite book</ref> Albendazole can be given with diethylcarbamazine to lower microfilaremia levels.<ref name=sweet-gibbs />
    • Toxocariasis, also called "visceral larva migrans", when caused by the dog roundworm Toxocara canis or cat roundworm T. catis. Corticosteroids can be added in severe cases, and surgery might be required to repair secondary damage.<ref name=AHFS2015 />
    • Trichinosis, when caused by Trichinella spiralis<ref name=tripathi /> or T. pseudospiralis. Albendazole has a similar efficacy to thiabendazole, but fewer side effects.<ref name=turner-horton /> It works best when given early, acting on the adult worms in the intestine before they generate larva that can penetrate the muscle and cause a more widespread infection. Corticosteroids are sometimes added on to prevent inflammation caused by dying larva.<ref name=yaffe-aranda />
    • Trichostrongyliasis, as an alternative to pyrantel pamoate.<ref name=AHFS2015 /><ref name="who_mpi_2"/> A single dose is sufficient for treatment.<ref name=yaffe-aranda />
    • Trichuriasis (whipworm infection),<ref name="who_mpi_2"/> sometimes considered as an alternative to mebendazole<ref name=AHFS2015 /><ref name=tripathi /> and sometimes considered to be the drug of choice. Only a single dose of albendazole is needed.<ref name=sweet-gibbs /> It can also be given with ivermectin.<ref name=finch>Template:Cite book</ref>
  • Giardiasis, as an alternative or adjunct to metronidazole, especially in children<ref name=AHFS2015 /><ref name=who-hiv>{{#invoke:citation/CS1|citation

|CitationClass=web }}</ref>

Though albendazole is effective in treating many diseases, it is only FDA-approved for treating hydatid disease caused by dog tapeworm larvae and neurocysticercosis caused by pork tapeworm larvae.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

Ivermectin/albendazoleEdit

When co-administered, ivermectin and albendazole act in synergy.<ref name="EMA PR 20250131" /> Ivermectin targets the parasite's nervous and muscular systems, causing paralysis, while albendazole disrupts the parasite's metabolism and microtubules.<ref name="EMA PR 20250131" /> This dual approach immobilizes and kills the parasite and improves the treatment's effectiveness.<ref name="EMA PR 20250131" />

In January 2025, the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA) adopted a positive scientific opinion for ivermectin/albendazole for the treatment of infections caused by several types of worm parasites including lymphatic filariasis, a neglected tropical disease.<ref name="EMA PR 20250131">{{#invoke:citation/CS1|citation |CitationClass=web }} Text was copied from this source which is copyright European Medicines Agency. Reproduction is authorized provided the source is acknowledged.</ref> Ivermectin/albendazole is indicated for use in people aged five years of age or older, for the treatment of soil-transmitted helminth infections, caused by different types of intestinal parasitic worms, which are spread through soil contaminated by human feces in areas with poor sanitation.<ref name="EMA PR 20250131" /> Among the worms responsible for these diseases are hookworms (Ancylostoma duodenale, Necator americanus), roundworms (Ascaris lumbricoides), whipworms (Trichuris trichiura) and a roundworm called Strongyloides stercoralis.<ref name="EMA PR 20250131" /> Ivermectin/albendazole is also indicated for the treatment of microfilaraemia (the presence of worm larvae in the blood) in people with lymphatic filariasis.<ref name="EMA PR 20250131" /> Lymphatic filariasis is a neglected tropical disease commonly known as elephantiasis, which impairs the lymphatic system and can lead to the abnormal enlargement of body parts, causing pain, severe disability and social stigma.<ref name="EMA PR 20250131" /> Ivermectin/albendazole is indicated for the treatment of cases of lymphatic filariasis caused by Wuchereria bancrofti, a parasite which is responsible for 90% of cases worldwide.<ref name="EMA PR 20250131" />

ContraindicationsEdit

Hypersensitivity to the benzimidazole class of compounds contraindicates its use.<ref name="who_mpi_2" />

Side effectsEdit

File:Taenia solium cyst.jpg
Close-up of a pork tapeworm cyst. Destruction of these cysts can cause inflammation.

The most common side effects of albendazole are experienced by over 10% of people and include headache and abnormal liver function.<ref name="MSR" /> Elevation of liver enzymes occurs in 16% of patients receiving treatment specifically for hydatid disease and goes away when treatment ends.<ref name="yaffe-aranda" /><ref name=dailymed>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> Liver enzymes usually increase to two to four times the normal levels (a mild to moderate increase).<ref name="farrar">Template:Cite book</ref> An estimated 1–10% of people experience abdominal pain, nausea or vomiting, dizziness or vertigo, increased intracranial pressure, meningeal signs, temporary hair loss, and fever. The headache, nausea, and vomiting are thought to be caused by the sudden destruction of cysticerci (tapeworm larvae), which causes acute inflammation.<ref name="jung">Template:Cite book</ref> Fewer than 1% of people get hypersensitivity reactions such as rashes and hives, leukopenias (drop in white blood cell levels) such as agranulocytosis and granulocytopenia, thrombocytopenia (reduced platelet count), pancytopenia (drop in white blood cells, red blood cells, and platelets), hepatitis, acute liver failure, acute kidney injury, irreversible bone marrow suppression, and aplastic anemia.<ref name="MSR" /><ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

Side effects can be different when treating for hydatid disease versus neurocysticercosis: for example, those being treated for the former are more likely to experience elevated liver enzymes and abdominal pain, while those being treated for the latter are more likely to experience headache.<ref name="dailymed" /> Treating hydatid disease can also unmask undiagnosed neurocysticercosis.<ref name="dailymed" /> People receiving albendazole for the treatment of neurocysticercosis can have neurological side effects such as seizures, increased intracranial pressure, and focal signs caused by the inflammatory reaction that occurs when parasites in the brain are killed. Steroids and anticonvulsants are often given with albendazole when treating neurocysticercosis to avoid these effects.<ref name="dailymed" /> Those being treated for retinal neurocysticercosis can face retinal damage if they are not first checked for ocular cysticeri, since changes to existing lesions in the eye by albendazole can cause permanent blindness.<ref name="yaffe-aranda" />

PregnancyEdit

Albendazole is a pregnancy class D drug in Australia. It is contraindicated in the first trimester of pregnancy, and should be avoided up to one month before conception. While studies in pregnant rats and rabbits have shown albendazole to be teratogenic,<ref name="drugs.com-pregnancy">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref name="parasitipedia-ricobendazole">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> albendazole has been found to be safe in humans during the second and third trimesters.<ref name=papich>Template:Cite book</ref><ref name=briggs>Template:Cite book</ref> It can, however, possibly cause infantile eczema when given during pregnancy.<ref name="wu-et-al">Template:Cite journal</ref>

In pregnant dogs, albendazole use has led to puppies with reduced weight and with cleft palates. Birds have lower rates of laying eggs and hatching when given albendazole.<ref name=parasitipedia-toxicity>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

Albendazole sulfoxide is secreted into breast milk at around 1.5% of the maternal dose, though oral absorption is poor enough that it is unlikely to affect nursing infants.<ref name="drugs.com-pregnancy" /><ref name=wiebe>Template:Cite book</ref>

OverdoseEdit

Because of its low solubility, albendazole often cannot be absorbed in high enough quantities to be toxic.<ref name=jung /> The oral LD50 of albendazole in rats was found to be 2,500 mg/kg.<ref name=parasitipedia-ricobendazole /> It takes 20 times the normal dose to kill a sheep, and 30 times the normal dose to kill cattle.<ref name=plumb>Template:Cite book</ref> Overdose affects the liver, testicles, and gastrointestinal tract (GI tract) the most. It can manifest with lethargy, loss of appetite, vomiting, diarrhea, intestinal cramps, dizziness, convulsions, and sleepiness.Template:Medcn There is no specified antidote.<ref name=parasitipedia-toxicity />

InteractionsEdit

The antiepileptics carbamazepine, phenytoin, and phenobarbital lower the plasma concentration and half-life of albendazole sulfoxide's R(+) enantiomer.<ref name="pmid12021623">Template:Cite journal</ref>

Antiepileptics and pharmacokinetics
of albendazole sulfoxide<ref name=finch />
Drug Change in AUC Change in Cmax
Carbamazepine 49% decrease 50–63% decrease
Phenobarbitol 61% decrease 50–63% decrease
Phenytoin 66% decrease 50–63% decrease

The antacid cimetidine heightens serum albendazole concentrations, increases the half-life of albendazole, and doubles albendazole sulfoxide levels in bile.<ref>Template:Cite journal</ref><ref name=dailymed /> It was originally thought to work by increasing albendazole bioavailability directly; however, it is now known that cimetidine inhibits the breakdown of albendazole sulfoxide by interfering with CYP3A4.<ref name=turner-horton /> The half-life of albendazole sulfoxide thus increases from 7.4 hours to 19 hours.<ref name=bennett>Template:Cite book</ref> This might be a helpful interaction on more severe cases, because it boosts the potency of albendazole.<ref name="pmid8192515">Template:Cite journal</ref> Paradoxically, cimetidine also inhibits the absorption of albendazole by reducing gastric acidity.<ref name=bennett />

Several other interactions exist. Corticosteroids increase the steady-state plasma concentration of albendazole sulfoxide;<ref name=yaffe-aranda /> dexamethasone, for example, can increase the concentration by 56% by inhibiting the elimination of albendazole sulfoxide.<ref name=dailymed /><ref name=jung /> The anti-parasitic praziquantel increases the maximum plasma concentration of albendazole sulfoxide by 50%,<ref name=dailymed /> and the anti-parasitic levamisole increases the AUC (total drug exposure) by 75%.<ref name=finch /> Grapefruit inhibits the metabolism of albendazole within the intestinal mucosa. Finally, long-term administration of the antiretroviral ritonavir, which works as a CYP3A4 inhibitor, decreases the maximum concentration of albendazole in the plasma as well as the AUC.<ref name=bennett />

PharmacologyEdit

File:Microtubule structure.png
A microtubule is composed of polymers of α- and β-tubulin.

Mechanism of actionEdit

Template:Cleanup section As a vermicide, albendazole causes degenerative alterations in the intestinal cells of the worm by binding to the colchicine-sensitive site of β-tubulin, thus inhibiting its polymerization or assembly into microtubules (it binds much better to the β-tubulin of parasites than that of mammals).<ref name=AHFS2015 /><ref name=dailymed /> Albendazole leads to impaired uptake of glucose by the larval and adult stages of the susceptible parasites, and depletes their glycogen stores. Albendazole also prevents the formation of spindle fibers needed for cell division, which in turn blocks egg production and development; existing eggs are prevented from hatching.<ref name=turner-horton /><ref>Template:Cite book</ref> Cell motility, maintenance of cell shape, and intracellular transport are also disrupted.<ref name=riviere>Template:Cite book</ref> At higher concentrations, it disrupts the helminths' metabolic pathways by inhibiting metabolic enzymes such as malate dehydrogenase and fumarate reductase, with inhibition of the latter leading to less energy produced by the Krebs cycle.<ref name=plumb /><ref name="parasitipedia-toxicity" /><ref name=waller-simpson>Template:Cite book</ref> Due to diminished ATP production, the parasite is immobilized and eventually dies.

Some parasites have evolved some resistance to albendazole by having a different set of amino acids constitute β-tubulin, decreasing the binding affinity of albendazole.<ref name=dailymed /> Some parasites (especially filarial nematodes) live in symbiosis with Wolbachia, a type of intracellular parasite bacteria. In such cases the Wolbachia are necessary to the survival of the parasitic worms.<ref name="Landmann-2019">Template:Cite journal</ref> Elimination of Wolbachia from these filarial nematodes generally results in either death or sterility of the host nematode.<ref name="pmid12684759">Template:Cite journal</ref>

PharmacokineticsEdit

To target intestinal parasites, which is the most common indication for prescription, albendazole is taken on an empty stomach to stay within the gut.<ref>Template:Cite book</ref>

Oral absorption of albendazole varies among species, with 1–5% of the drug being successfully absorbed in humans, 20–30% in rats, and 50% in cattle.<ref name=dayan/>

The absorption also largely depends on gastric pH. People have varying levels of gastric pHs on empty stomachs, and thus absorption from one person to another can vary wildly when taken without food.<ref name=gouma /> Generally, the absorption in the GI tract is poor due to albendazole's low solubility in water.<ref name=AHFS2015 /> It is, however, better absorbed than other benzimidazole carbamates.<ref name=finch /> Food stimulates gastric acid secretion, lowering the pH and making albendazole more soluble and thus more easily absorbed.<ref name=bennett /> Oral absorption is especially increased with a fatty meal, as albendazole dissolves better in lipids, allowing it to cross the lipid barrier created by the mucus surface of the GI tract.<ref name="riviere" /><ref name=dayan>Template:Cite journal</ref>

Absorption is also affected by how much of the albendazole is degraded within the small intestine by metabolic enzymes in the villi.<ref name="gouma" />

File:Albendazole metabolism.svg
General metabolism of albendazole and its sulfoxides

The pharmacokinetics of albendazole differ slightly between men and women: women have a lower oral clearance and volume of distribution, while men have a lower serum peak concentration.<ref name="bennett" />

Albendazole undergoes very fast first-pass metabolism in all species, such that the unchanged drug is undetectable in plasma.<ref name="dayan" /> Most of it is oxidized into albendazole sulfoxide (also known as ricobendazole and albendazole oxide<ref name="parasitipedia-ricobendazole"/><ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>) in the liver by cytochrome P450 oxidases (CYPs) and a flavin-containing monooxygenase (FMO),<ref name="rawden">Template:Cite journal</ref> which was discovered later.<ref>Template:Cite journal</ref> In humans, the cytochrome P450 oxidases are thought to include CYP3A4<ref>Template:Cite book</ref> and CYP1A1,<ref name="dayan" /> while those in the rats are thought to be CYP2C6 and CYP2A1.<ref name="capece" />

Oxidation to albendazole sulfoxide by FMO produces R(+) enantiomers, while oxidation the cytochromes and by some enzymes in the gut epithelium produce S(−). Different species produce the R(+) and S(−) enantiomers in different quantities; humans, dogs, and most other species<ref name="capece" /> produce the R(+) enantiomer more (with the human AUC ratio being 80:20).<ref name="jung" /><ref name="bennett" /><ref name="dayan" /> Compared to the S(−) enantiomer, the R(+) has greater pharmacological activity, lasts longer in the bloodstream, is found in higher concentrations in the infected host tissues, and is found in higher concentrations within the parasites themselves.<ref name="capece">Template:Cite journal</ref><ref name="riviere" /> Some albendazole is also converted to hydroxyalbendazole, mainly by CYP2J2.<ref name="wu-et-al" /><ref>Template:Cite journal</ref>

For systemic parasites, albendazole acts as a prodrug, while albendazole sulfoxide reaches systemic circulation and acts as the real antihelminthic.<ref name="turner-horton" /> Albendazole sulfoxide is able to cross the blood–brain barrier and enter the cerebrospinal fluid at 43% of plasma concentrations; its ability to enter the central nervous system allows it to treat neurocysticercosis.<ref name="bennett" />

Albendazole sulfoxide is converted to the inactive albendazole sulfone by cytochrome P450 oxidases, thought to include CYP3A4<ref name="bennett" /> or CYP2C.<ref name="turner-horton" /> Other inactive metabolites include: 2-aminosulfone, ω-hydroxysulfone, and β-hydroxysulfone.<ref name="rawden" /><ref name="jung" /> The major final metabolites that are excreted by humans are:<ref name="turner-horton" />

  • methyl [5-(propylsulfonyl-1H-benzimidazol-2-yl)] carbamate,
  • methyl [6-hydroxy 5-(n-propylsulfonyl)-1H-benzimidazole-2-yl)] carbamate,
  • methyl [5-(n-propylsulfinyl)-1H-benzimidazole-2-yl)] carbamate,
  • 5-(n-propylsulfonyl)-1H-benzimidazole-2-yl amine, and
  • 5-(n-propysulfinyl)-1H-benzimidazole-2-yl amine.

There are also some minor hydroxylated sulfated or glucuronidated derivatives.<ref name="turner-horton" /> No unchanged albendazole is excreted, as it is metabolized too quickly.<ref name="MSR" />

In humans, the metabolites are excreted mostly in bile, with only a small amount being excreted in urine (less than 1%) and feces.<ref name=MSR >{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref name=turner-horton /> In ruminants, 60–70% of the metabolites are excreted in urine.<ref name=parasitipedia-toxicity />

Like all benzimidazoles, albendazole has no residual effect, and thus protects poorly against reinfestations.<ref name=parasitipedia-ricobendazole />

HistoryEdit

Albendazole, patented in 1975, was invented by Robert J. Gyurik and Vassilios J. Theodorides and assigned to SmithKline Corporation.<ref>Template:Cite patent Template:Webarchive [1]</ref><ref>Template:Cite patent Template:Webarchive [2] Template:Webarchive</ref> It was introduced in 1977 as an antihelminthic for sheep in Australia, and was registered for human use in 1982.<ref name="yaffe-aranda" /><ref name=turner-horton />

Society and cultureEdit

EconomicsEdit

The pharmaceutical company Amedra increased the price after purchasing the rights to the drug, instead of lowering it as generics are predicted to do, drawing criticism from patients' rights advocates.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

In 2013, GlaxoSmithKline donated 763 million albendazole tablets for the treatment and prevention of parasitic infections in developing countries, bringing the total to over 4 billion tablets donated since 1998.<ref>Template:Cite journal</ref>

Brand namesEdit

Brand names include: Albenza,<ref name=dailymed /> Alworm, Andazol, Eskazole, Noworm, Zentel, Alben-G, ABZ, Cidazole, Wormnil etc.

ResearchEdit

Albendazole and related compounds or metabolites like albendazole sulfone (ALB-SO2) exhibit antibacterial effects via an unknown, possibly FtsZ-related, mechanism. It inhibits division of Wolbachia and Mycobacterium tuberculosis, turning them into a long "filament" shape as they grow and fail to divide. Since Brugia malayi relies on symbiotic Wolbachia, this would mean that albendazole is targeting both the worm and its essential symbioant.<ref name=Wolb>Template:Cite journal</ref>

Veterinary useEdit

Albendazole is mainly used in cattle and sheep, but has found some use in cats and dogs as well;<ref name=papich /> it is also used in ratite birds for flagellate parasites and tapeworms. It is also used off-label to treat endoparasites in goats and pigs.<ref name=plumb />

Albendazole use in animals<ref name=plumb /><ref name=papich /><ref name=bowman>Template:Cite book</ref><ref name=parasitipedia-use>{{#invoke:citation/CS1|citation
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Cattle Sheep Others
Platyhelminthes (flatworms)
Trematodes
Dicrocoelium (liver flukes) D. dendriticum (lancet liver fluke)<ref name=divers>Template:Cite book</ref> D. dendriticum<ref name="parasitipedia-dosing" />
Fasciola (liver flukes) F. hepatica F. hepatica For F. hepatica and F. gigantica in people<ref name=AHFS2015 />
Fascioloides (liver flukes) F. magna<ref name=divers /> F. magna Also for F. magna in South American camelids (ex. llama and alpaca)<ref name="parasitipedia-dosing" />
Paragonimus (lung flukes) For P. kellicotti in cats and dogs<ref name="parasitipedia-dosing" />
Platynosomum For Platynosomum infections in cats
Opisthorchiidae For Opisthorchiidae infections in cats
Cestodes (tapeworms)
Echinococcus For Echinococcus cysts in horses and humans<ref name="parasitipedia-dosing" /><ref name=AHFS2015 />
Moniezia M. expansa
M. benedini
M. expansa
 
Taenia T. saginata larvae For T. saginata, T. solium, and T. crassiceps in humans<ref name=tripathi /><ref name=wu /> and Taenia infections in dogs<ref>Template:Cite book</ref>
Thysanosoma T. actinoides
Nematodes (roundworms)
Ancylostoma For Ancylostoma infections in dogs, cats, and humans<ref name="parasitipedia-dosing" /><ref name=AHFS2015 />
Bunostomum B. phlebotomum
Capillaria For causative agents of various forms of capillariasis in cats and dogs (including C. philippinensis, C. hepatica, C. aerophila, and C. plica) and intestinal capillariasis (C. philippinensis) in humans.
Chabertia C. ovina
Cooperia C. oncophora
C. punctata
C. oncophora
 
Dictyocaulus (lungworm) D. viviparus D. filaria For D. amfieldi infections in horses
Filaroides (lungworm) For F. hirthi and F. osleri in dogs
Haemonchus H. contortus
H. placei
H. contortus
 
Marshallagia M. marshalli
Metastrongylus For M. apri in swine
Nematodirus N. spathiger
N. helvetianus
N. spathiger
N. filicollis
Parascaris For P. equorum in horses<ref name=parasitipedia-use />
Ostertagia O. ostertagi O. circumcincta For O. bifurcum in humans
Oesophagostomum O. radiatum O. columbianum
Strongyloides For S. stercoralis in dogs and humans<ref name=AHFS2015 /><ref name="parasitipedia-dosing" />
Strongylus For S. equinus in horses<ref name=parasitipedia-dosing />
Toxocara For T. canis infections in dogs<ref name="parasitipedia-dosing">{{#invoke:citation/CS1|citation CitationClass=web

}}</ref> and toxocariasis in humans (caused by T. canis and T. cati)

Trichostrongylus T. axei
T. colubriformis
T. axei
T. colubriformis
For any Trichostrongylus infection in humans
Trichuris (whipworm) Most species, but those usually found in cattle are:<ref name="parasitipedia-trichuris" />
T. discolor
T. globulosa
T. ovis
Most species, but those usually found in sheep are:<ref name="parasitipedia-trichuris" />
T. discolor
T. globulosa
T. ovis
Albendazole is also used for Trichuris infections in humans (usually T. trichiura, causative agent of trichuriasis), dogs (usually T. vulpis and T. campanula), cats (usually T. serrata and T. campanula), pigs (usually T. suis), and other ruminants (same species as those found in cattle and sheep).<ref name="parasitipedia-trichuris">{{#invoke:citation/CS1|citation CitationClass=web

}}</ref>

Other
Encephalitozoon For E. cuniculi infections (microsporidiosis) in humans and rabbits
Giardia G. lamblia (causative agent of giardiasis) Also treats giardiasis in humans, dogs, and small mammals
Leishmania Treats leishmaniasis, caused by various species of Leishmania, in dogs

Albendazole has been used as an antihelminthic and for control of flukes in a variety of animal species, including cattle, sheep, goats, swine, camels, dogs, cats, elephants, poultry, and others.<ref name=parasitipedia-toxicity /><ref>Template:Cite book</ref> Side effects include anorexia in dogs and lethargy, depression, and anorexia in cats,<ref name=plumb /> with more than 10% of dogs and cats having anorexia.<ref name=wiebe /> Of dogs and cats, 1–10% experience elevated liver enzymes, nausea, vomiting, and diarrhea. Less than 1% experience neutropenia or aplastic anemia, though these require a use of at least 5 days.<ref name=wiebe /> While it is also associated with bone marrow suppression and toxicity in cats and dogs at high doses, albendazole has a higher margin of safety in other species.<ref name=papich /><ref name=bowman /> Thus, it is usually only prescribed in cats and dogs when an infection is present that is resistant to the commonly prescribed metronidazole and fenbendazole.<ref name=webster>Template:Cite book</ref>

It is extensively used for ruminant livestock in Latin America.<ref name=parasitipedia-ricobendazole /> It is marketed for this purpose by Zoetis (formerly Pfizer Animal Health) in numerous countries (including the United States and Canada) as Valbazen in oral suspension and paste formulations;<ref name=plumb /><ref name=papich /> by Interchemie in the Netherlands and elsewhere as Albenol-100; by Channelle Animal Health Ltd. in the United Kingdom as Albex; and by Ravensdown in New Zealand (as Albendazole). Although most formulations are administered orally, Ricomax (ricobendazole, or albendazole sulfoxide) is administered by subcutaneous injection.Template:Citation needed

Albendazole has greater bioavailability in ruminants: some albendazole sulfoxide, when released back into the rumen, is reduced to albendazole by the resident microbiota, with a preference of the (+) enantiomer being the substrate.<ref name=capece /><ref name=riviere /> Cats and dogs, having no rumen reservoir, sometimes need higher or more frequent doses as compared to ruminants. In dogs, albendazole sulfoxide is detectable in the plasma for less than 12 hours, but in sheep and goats, it remains at measurable levels for around three days.<ref name=parasitipedia-toxicity />

MeatEdit

Template:More citations needed The limitations in early pregnancy are due to a limited period during which teratogenic effects may occur. Summarized research data relating to the durations of these preslaughter and early pregnancy periods when albendazole should not be administered are found in US FDA NADA 110-048 (cattle) and 140-934 (sheep). Some data and inferences regarding goats are found in US FDA Supplemental NADA 110-048 (approved 24 January 2008).

Maximum residue limits (MRLs) for albendazole in food, adopted by the FAO/WHO Codex Alimentarius in 1993, are 5000, 5000, 100, and 100 micrograms per kilogram of body weight (μg/kg) for kidney, liver, fat, and muscle, respectively, and 100 μg/L for milk. For analysis purposes, MRLs of various nations may pertain to concentration of a marker substance which has been correlated with concentrations of the administered substance and its metabolized products. For example, in Canada, the marker substance specified by Health Canada is albendazole-2-aminosulfone, for which the MRL in liver of cattle is 200 μg/kg.

There is a 27-day cattle withdrawal time for meat.<ref name=papich />

ReferencesEdit

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