albendazole

Brand: Albenza

Prototype Drug
Drug Class: benzimidazole antiparasitic
Drug Family: antiparasitic
Subclass: broad-spectrum benzimidazole
Organ Systems: infectious-disease

Mechanism of Action

Binds helminth beta-tubulin, preventing tubulin polymerization; disrupts microtubule function, impairs glucose uptake and energy metabolism, and inhibits secretory vesicle function; the active metabolite albendazole sulfoxide has high tissue penetration for cystic disease.

beta-tubulin of helminths and protozoa

Indications

  • neurocysticercosis (Taenia solium)
  • cystic echinococcosis (hydatid disease)
  • filariasis
  • strongyloidiasis
  • ascariasis, hookworm, pinworm, whipworm (standard intestinal helminths)
  • giardiasis (alternative)

Contraindications

  • albendazole hypersensitivity
  • pregnancy (teratogenic — verify negative pregnancy test before initiating)

Adverse Effects

Common

  • elevated liver enzymes
  • abdominal pain
  • nausea

Serious

  • hepatotoxicity
  • bone marrow suppression (agranulocytosis)
  • Steven-Johnson syndrome (rare)
  • CNS effects in neurocysticercosis (seizures from dying larvae)

Pharmacokinetics (ADME)

Absorption poorly absorbed orally; high-fat meal increases absorption by ~5-fold; always administer with fatty food
Distribution albendazole sulfoxide (active metabolite) distributes widely including CSF, cyst fluid
Metabolism extensive first-pass to albendazole sulfoxide (active) and sulfone (inactive)
Excretion biliary/fecal (primarily); renal minor
Half-life 8–12 hours (albendazole sulfoxide)
Onset 2–5 hours
Peak 2–5 hours
Duration 28-day cycles (neurocysticercosis, echinococcosis)
Protein Binding 70%
Vd large

Drug Interactions

Drug / Agent Mechanism Severity
cimetidine increases albendazole sulfoxide levels ~50%; potentially beneficial for systemic infections minor
dexamethasone increases albendazole sulfoxide levels ~56%; co-administered for neurocysticercosis to reduce inflammation minor
anticonvulsants (carbamazepine, phenytoin) reduce albendazole levels; monitor response moderate

Nursing Considerations

  1. Administer with a fatty meal for systemic infections (neurocysticercosis, echinococcosis) to maximize absorption; for simple intestinal infections, standard administration suffices.
  2. For neurocysticercosis, co-administer corticosteroids (dexamethasone) to prevent CNS inflammatory reactions from dying parasites; monitor for seizure activity.
  3. Obtain baseline LFTs and CBC before starting therapy; monitor monthly — both hepatotoxicity and agranulocytosis can occur.
  4. Confirm negative pregnancy test before prescribing; use contraception during and for 3 days after therapy.

Clinical Pearls

  • Albendazole's active metabolite (sulfoxide) penetrates to echinococcal cyst fluid and CSF at therapeutic concentrations, enabling treatment of systemic cystic infections that mebendazole cannot adequately reach due to poor absorption.
  • For neurocysticercosis, antiparasitic therapy is controversial in purely calcified lesions; it is indicated for viable or transitional cysts, and should always be combined with corticosteroids and anticonvulsants to manage the inflammatory response to dying parasites.

Safety Profile

Pregnancy contraindicated
Lactation use-with-caution
Renal Adjustment Not required
Hepatic Adjustment Required
TDM Not required