Definição e significado de Albendazole

Albendazole

Systematic (IUPAC) name
Methyl [6-(propylthio)-1H-benzoimidazol-2-yl]carbamate
Clinical data
Trade names	Albenza
AHFS/Drugs.com	monograph
MedlinePlus	a610019
Pregnancy cat.	D
Legal status	prescription
Routes	only oral route
Pharmacokinetic data
Metabolism	oxidation of sulfur atom to sulfoxide, the active metabolite
Half-life	About 8.5 h
Identifiers
CAS number	54965-21-8 Y
ATC code	P02CA03 QP52AC11
PubChem	CID 2082
DrugBank	DB00518
ChemSpider	1998 Y
UNII	F4216019LN Y
KEGG	D00134 Y
ChEBI	CHEBI:16664 Y
ChEMBL	CHEMBL1483 Y
NIAID ChemDB	007895
Chemical data
Formula	C12H15N3O2S
Mol. mass	265.333 g/mol
SMILES O=C(OC)Nc2nc1ccc(SCCC)cc1n2
InChI InChI=1S/C12H15N3O2S/c1-3-6-18-8-4-5-9-10(7-8)14-11(13-9)15-12(16)17-2/h4-5,7H,3,6H2,1-2H3,(H2,13,14,15,16) Y Key:HXHWSAZORRCQMX-UHFFFAOYSA-N Y
Y (what is this?)  (verify)

Albendazole, marketed as Albenza, Eskazole, Zentel, Andazol and Alworm, is a member of the benzimidazole compounds used as a drug indicated for the treatment of a variety of worm infestations. Although this use is widespread in the United States, the U.S. Food and Drug Administration (FDA) has not approved albendazole for this indication. It is marketed by Amedra Pharmaceuticals. Albendazole was first discovered at the SmithKline Animal Health Laboratories in 1972. It is a broad spectrum anthelmintic, effective against: roundworms, tapeworms, and flukes of domestic animals and humans.^[1]

  Main uses

It is effective first line of treatment against:

• Flatworms
  • Flukes/trematodes
    • Fasciolosis
  • Tapeworm/cestodes
    • Cysticercosis
    • Echinococcosis^[2]
• Nematodes
  • Enterobiasis (pinworm infection)
  • Trichuriasis (whipworm infection)
  • Ascariasis
  • Hookworm
  • Cutaneous larva migrans (caused by Ancylostoma)
  • Filariasis

  Other uses

  Discarded bottles of albendazole distributed in Africa

In Africa, albendazole (donated by GlaxoSmithKline) is being used to treat lymphatic filariasis as part of efforts to stop transmission of the disease.^[3] In sub-Saharan Africa, albendazole is used in conjunction with ivermectin, and elsewhere in the world, the medicine is used in combination with diethylcarbamazine.^[3]

In Brazil and other countries it is used against giardiasis.^[4]

  Mode of action

As a vermicidal, albendazole causes degenerative alterations in the tegument and intestinal cells of the worm by binding to the colchicine-sensitive site of tubulin, thus inhibiting its polymerization or assembly into microtubules. The loss of the cytoplasmic microtubules leads to impaired uptake of glucose by the larval and adult stages of the susceptible parasites, and depletes their glycogen stores. Degenerative changes in the endoplasmic reticulum, the mitochondria of the germinal layer, and the subsequent release of lysosomes result in decreased production of adenosine triphosphate (ATP), which is the energy required for the survival of the helminth. Due to diminished energy production, the parasite is immobilized and eventually dies.

Albendazole also has been shown to inhibit the enzyme fumarate reductase, which is helminth-specific. This action may be considered secondary to the effect on the microtubules due to the decreased absorption of glucose. This action occurs in the presence of reduced amounts of nicotinamide-adenine dinucleotide in reduced form (NADH), which is a coenzyme involved in many cellular oxidation-reduction reactions.

Albendazole has larvicidal effects in necatoriasis and ovicidal effects in ascariasis, ancylostomiasis, and trichinosis.

  Dosage

Albendazole is only given orally (PO).

  Hydatid disease (Echinococcosis)

• Patients 60 kg or greater: 400 mg twice daily, with meals.
• Patients less than 60 kg: 15 mg/kg/day given in divided doses twice daily with meals (maximum total daily dose 800 mg).
• Treatment interval: 28-day cycle followed by a 14-day albendazole-free interval, for a total of 3 cycles.

NOTE: When administering albendazole in the pre- or post-surgical setting, optimal killing of cyst contents is achieved when 3 courses of therapy have been given.

  Neurocysticercosis

• Patients 60 kg or greater: 400 mg twice daily, with meals.
• Patients less than 60 kg: 15 mg/kg/day given in divided doses twice daily with meals (maximum total daily dose 800 mg).
• Treatment interval: 8–30 days.

Note: Patients being treated for neurocysticercosis should receive appropriate steroid and anticonvulsant therapy as required. Oral or intravenous corticosteroids should be considered to prevent cerebral hypertensive episodes during the first week of treatment.

  Filaria

Single dose of 400 mg. For Filariasis, note that Albendazole has no effect on the adult worms (Lymphatic filariasis and onchocerciasis Mark J Taylor, Achim Hoerauf, Moses Bockarie, 2010, Lancet). Filariasis, albendazole and/or disintegrating filariae can affect the lymphatic system.

  Side effects

Albendazole may cause abdominal pain, dizziness, headache, fever, nausea, vomiting, or temporary hair loss.

In rare cases it may cause persistent sore throat, severe headache, seizures, vision problems, yellowing eyes or skin, dark urine, stomach pain, easy bruising, mental/mood changes, very stiff neck, change in amount of urine. Elevation of liver enzymes during treatment is a common side effect, but in rare cases there have also been reports of acute liver failure. Allergic reactions are also possible.

Rarely Albendazole has been reported to cause marrow suppression, agranulocytosis or aplastic anemia which may be permanent.^[5] The risk of developing this side effect seems to be increased in patients with liver disease, including echinococcal cysts. Because of this dangerous side effect it is important to regularly monitor complete blood counts.

  Drug interactions

  Antiepileptics

The drugs carbamazepine, phenytoin and phenobarbital lower the plasmatic concentration and the half life of albendazole.^[6]

  Antacids/histamine H₂ antagonists

The drug cimetidine heightens serum albendazole concentrations, and increases the half life of albendazole.^[7]

This might be a helpful interaction on more severe cases, because it boosts the potency of albendazole.^[8]

  Contraindications

Hypersensitivity to the benzimidazole class of compounds.

  Pregnancy class

D (Australia) - Do not take when pregnant, and do not become pregnant for one month after taking this drug. Pharmacokinetic studies have shown that trace amounts of albendazole appears in semen. Given this potential for teratogenicity, the manufacturers advise that the male sexual partner should also use adequate protection.

  See also

• Mebendazole
• Eradication of infectious disease
• Neglected diseases

  References

  External links

• The Carter Center Lymphatic Filariasis Elimination Program
• MedicineNet article
• Albenza description at RxList