al-BEN-da-zole

Therapeutic Classification:

• Neurocysticercosis.
• Hydatid disease.

• Inhibits tubulin polymerization, resulting in the loss of cytoplasmic microtubules.

• Death of affected larval form of susceptible parasites.

Spectrum:

• Echinococcus granulosus (dog tapeworm).
• Taenia solium (pork tapeworm).

Absorption: Poorly absorbed following oral administration because of extensive first-pass hepatic metabolism, resulting in rapid conversion to albendazole sulfoxide, the active metabolite.

Distribution: Widely distributed.

Protein Binding: 70% bound to plasma proteins.

Metabolism/Excretion: After conversion to the sulfoxide metabolite, further hepatic metabolism to inactive compounds occurs. <1% excreted in urine; excretion is primarily via bile.

Half-life: Albendazole sulfoxide: 8–12 hr.

(blood levels of albendazole sulfoxide)

Contraindicated in:

• Hypersensitivity
• Hepatic dysfunction
• Neurocysticercosis involving the retina
• OB: Pregnancy (may cause fetal harm).

Use Cautiously in:

• Lactation: Use while breastfeeding only if potential maternal benefit justifies potential risk to infant
• Women of reproductive potential
• Pedi: Has been used safely in children <6 yr.

Derm: reversible alopecia.

GI: ↑liver enzymes (↑ in hydatid disease), abdominal pain (hydatid disease only), nausea/vomiting (↑ in neurocysticercosis).

Hemat: AGRANULOCYTOSIS, GRANULOCYTOPENIA, PANCYTOPENIA.

Neuro: headache (↑ in neurocysticercosis), ↑ intracranial pressure (↑ in neurocysticercosis), dizziness/vertigo, meningeal signs (in neurocysticercosis only).
Misc: fever (hydatid disease only).

Drug-Drug:

• Dexamethasone and praziquantel may ↑ levels.
• May ↓ levels of theophylline.

Drug-Food:

• Levels ↑ by concurrent ingestion of a high-fat meal.

Hydatid Disease

• PO (Adults and Children 60 kg): 400 mg twice daily with meals for 28 days, followed by 14 days off, for a total of 3 cycles.
• PO (Adults and Children <60 kg): 15 mg/kg/day given in 2 divided doses with meals (maximum daily dose = 800 mg) for 28 days, followed by 14 days off, for a total of 3 cycles.

Neurocysticercosis

• PO (Adults and Children 60 kg): 400 mg twice daily with meals for 8–30 days.
• PO (Adults and Children <60 kg): 15 mg/kg/day given in 2 divided doses with meals (maximum daily dose = 800 mg) for 8–30 days.

(Generic available)

• Tablets: 200 mg;

• Neurocysticercosis: Administer corticosteroids for 1–2 days prior to starting albendazole to minimize inflammatory reactions. Concurrent corticosteroid and anticonvulsant therapy should be administered during the first wk of albendazole therapy to prevent cerebral hypertension and potential seizures.
  • Ophthalmic examinations should be performed before therapy to determine presence of retinal lesions.

• Verify negative pregnancy test before starting therapy.Monitor liver function tests before start of each treatment and at least every 2 wk during treatment. If enzymes are significantly ↑, discontinue albendazole; may be reinstituted when levels return to pretreatment levels.
  • Monitor WBC count before each 28-day cycle and every 2 wk during each 28–day cycle. Decrease in WBC count is usually reversible upon discontinuation of therapy. Therapy may be continued if decrease is moderate and does not progress. If clinically significant ↓; discontinue therapy.

• Administer with food (preferably high in fat content). Tablets may be crushed or chewed; follow with water.

• Instruct patient to take medication with a fatty food exactly as directed.
• Caution patients to notify health care professional if signs of hepatotoxicity (e.g. jaundice, dark urine, light-colored bowel movement, anorexia, nausea, abdominal pain) occur.
• Advise patient to use contraception during and for at least 3 days after last dose. May cause fetal harm. Advise patient to notify health care professional if pregnancy is planned or suspected or if breastfeeding.
• Emphasize the importance of regular blood tests to check WBCs and hepatic function.

• Resolution of cysts in neurocysticercosis or hydatid disease.

Albenza