Liver albendazole

Albendazole is variably absorbed after oral administration. A fatty meal enhances absorption. After a 400-mg oral dose, albendazole cannot be detected in plasma, because the drug is rapidly metabolized in the liver to its sulfoxide, which has potent anthelmintic activity. Both the (-t-) and (-) enantiomers of albendazole sulfoxide are formed the (-t-) enantiomer reaches much higher peak plasma concentrations and is cleared much more slowly. Albendazole sulfoxide is -70% bound to plasma proteins and has a variable plasma tj (-4-15 hours). It is well distributed into various tissues including hydatid cysts, probably explaining its greater efficacy for tissue-dwelling helminths. Formation of albendazole sulfoxide is catalyzed by both microsomal flavin monooxygenase and CYP isoforms in the liver. Albendazole metabolites are excreted mainly in the urine. 

Albendazole (Albenza) interferes wiHi Hie synHiesis of the parasite s microtubules, resulting in deatii of susceptible larva This drug is used to treat larval forms of pork tapeworm and to treat liver, lung, and peritoneum disease caused by the dog tapeworm. 

Albendazole is given orally and is poorly and variably absorbed (<5%) because of its poor water solubility. Oral bioavaUabihty is increased as much as five times when the drug is given with a fatty meal instead of on an empty stomach. Concurrent treatment with corticosteroids increases plasma concentrations of albendazole. The drug is rapidly metabolized in the liver to an active sulfoxide metabolite. The half fife of the metabolites is 8 to 12 hours. 

Clonorchis sinensis (liver fluke) Opisthorchis species Praziquantel Albendazole... 

Albendazole is a benzimidazole carbamate. After oral administration, it is erratically absorbed (increased with a fatty meal) and then rapidly undergoes first-pass metabolism in the liver to the active metabolite albendazole sulfoxide. It reaches variable maximum plasma concentrations about 3 hours after a 400-mg oral dose, and its plasma half-life is 8-12 hours. The sulfoxide is mostly protein-bound, distributes well to tissues, and enters bile, cerebrospinal fluid, and hydatid cysts. Albendazole metabolites are excreted in the urine. 

When used for 1-3 days, albendazole is nearly free of significant adverse effects. Mild and transient epigastric distress, diarrhea, headache, nausea, dizziness, lassitude, and insomnia can occur. In long-term use for hydatid disease, albendazole is well tolerated, but it can cause abdominal distress, headaches, fever, fatigue, alopecia, increases in liver enzymes, and pancytopenia. 

Blood counts and liver function studies should be monitored during long-term therapy. The drug should not be given to patients with known hypersensitivity to other benzimidazole drugs or to those with cirrhosis. The safety of albendazole in pregnancy and in children younger than 2 years of age has not been established. 

When an oral suspension of albendazole was given via the drinking water to laying hens, both the parent compound and the sulfoxide and sulfone metabolites were rapidly eliminated from the tissues. At 96 h after treatment, liver con-... 

Residue depletion studies in dairy cattle and sheep showed that the proportions of the major sulfoxide, sulfone, and 2-aminosulfone metabolites of albendazole change dramatically over a period of days in the case of tissues or hours in the case of milk, with albendazole sulfoxide predominating at early time points and albendazole sulfone and albendazole-2-aminosulfone appearing later (16). From day 4 onwards, more than 95% of the residues in bovine liver and kidney was in the bound form, but tissue binding in sheep tissues was less extensive. 

After subcutaneous or intramuscular injection of netobimin into cattle, absorption was rapid but plasma levels of radioactivity were lower than those achieved following oral administration. This indicates that absorption occurred prior to the conversion to albendazole since high levels of parent drug were found in plasma and milk soon after the injection. On the other hand, at 12 h after the injection the parent drug could not be detected at the injection site or in liver. 

When sheep were similarly U eated with an oral dose of netobimin, total residues in all tissues except milk were generally lower than those in cattle. Albendazole, albendazole sulfoxide, albendazole sulfone, and albendazole-2-aminosulfone accounted for nearly all the residues in muscle and fat tissues at time points ranging from 18 h to 20 days. In liver and kidney, however, these metabolites accounted for a lower proportion of the total residues as time progressed, indicating the presence of bound residues. 

Albendazole 556.34 Albendazole 2-amino- Cattle Liver (target) - 200... 

Albendazole (Albenza) is primarily used to treat infections caused by the larval form of certain cestodes (tapeworms). These infections often cause cysts (hydatid disease) in the liver, lungs, and other tissues albendazole is used as an adjunct to the surgical removal of these cysts or as the primary treatment if these cysts are inoperable. This drug is also effective against many gastrointestinal roundworms and hookworms, and is typically used as a secondary agent if other anthelmintics are not effective in treating these infections. 

Liver samples from cattle (292) and pigs (394) were found to be free of any detectable residues of these compounds. Of the 529 sheep liver samples analysed only one was found to have detectable residues (3,500/xg/kg, albendazole) which are significantly above the MRL for this compound (1000/xg/kg). 

Effect of albendazole on recurrent and residual alveolar echinococcosis of the liver after surgery. Hepatology 1997 25 528-531... 

Hydatid disease is a common zoonosis caused by the larval cysts of Echinococcus granulosus. Hydatid cysts most commonly form in the liver, but can occur in any organ. The management and operative comphcations in 70 patients with hydatid disease aged 10-78 years have been studied retrospectively to assess the impact of albendazole and praziquantel compared with surgery (6). In all,... 

The epidemiology, clinical presentation, and treatment of alveolar echinococcosis of the liver have been described in French patients followed between 1972 and 1993 (5). From 1982 benzimidazoles were used. Of 117 patients, 72 took either albendazole or mebendazole for 4—134 months. The most common adverse effects were an increase in alanine transaminase activity to more than five times the top of the reference range (in six patients taking albendazole and in three taking mebendazole). Neutropenia (leukocyte count below 1.0 x 10 /1) occurred in two patients taking albendazole. Alopecia occurred in four patients taking mebendazole. Minor adverse effects of albendazole included malaise, anorexia, and digestive intolerance in one patient each. In 13 patients treatment had to be withdrawn because of adverse effects n —10) or non-adherence to therapy (n = 3). 

Galtier, P., Alviniere, M. Delatour, P. (1986) In vitro sulfoxidation of albendazole by ovine liver microsomes assay and frequency of various xenobiotics. American Journal of Veterinary Research, 47, 447-450. 

Souhaili El Amri, H., Mothe, O., Totis, M. et al. (1988) Albendazole sulfonation by rat liver cytochrome P-450c. Journal of Pharmacology and Experimental Therapeutics, 246, 758-764. 

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