Albendazole: Comprehensive Broad-Spectrum Anthelmintic Therapy
Albendazole
Albendazole is a benzimidazole carbamate anthelmintic agent with broad-spectrum activity against a wide range of parasitic helminth infections. It exerts its therapeutic effect through selective inhibition of microtubule polymerization in susceptible parasites, leading to impaired glucose uptake and eventual depletion of energy stores. This mechanism results in immobilization and death of helminths, making it a cornerstone in both individual treatment and public health initiatives for parasitic control. Its lipophilic properties ensure excellent tissue penetration, including the central nervous system, making it particularly effective against tissue-dwelling parasites.
Features
- Active pharmaceutical ingredient: Albendazole 200mg or 400mg tablets
- Pharmacologic class: Benzimidazole anthelmintic
- Mechanism: Selective inhibition of parasite β-tubulin polymerization
- Bioavailability: Enhanced approximately 5-fold when administered with fatty meals
- Metabolism: Extensive first-pass metabolism to active sulfoxide metabolite
- Elimination: Primarily biliary excretion with renal clearance of metabolites
Benefits
- Eradicates multiple intestinal and tissue-dwelling helminth infections through a single therapeutic agent
- Demonstrates ovicidal, larvicidal, and vermicidal activity against susceptible parasites
- Provides systemic coverage for extra-intestinal parasitic infections including neurocysticercosis and hydatid disease
- Supports public health parasite control programs through effective mass drug administration
- Offers flexible dosing regimens adaptable to various patient populations and infection types
- Reduces parasite transmission through decreased egg production and viability
Common use
Albendazole is indicated for the treatment of various parasitic infections including soil-transmitted helminthiases (ascariasis, trichuriasis, hookworm infections), enterobiasis, strongyloidiasis, and clonorchiasis. It is also employed in the management of systemic parasitic diseases such as neurocysticercosis caused by Taenia solium larvae and hydatid disease caused by Echinococcus granulosus. The World Health Organization includes albendazole in its Model List of Essential Medicines for its efficacy in helminth control programs.
Dosage and direction
Dosage varies according to the specific parasitic infection being treated. For intestinal helminths: 400mg as a single dose for adults and children over 2 years (200mg for children 1-2 years). For neurocysticercosis: 400mg twice daily with meals for 8-30 days. For hydatid disease: 400mg twice daily with meals for 28-day cycles followed by 14-day drug-free intervals, typically for 3 cycles. Administration with a fatty meal significantly enhances bioavailability. Tablets should be swallowed whole with water; chewing or crushing is not recommended.
Precautions
Hepatic function should be monitored during prolonged therapy due to potential hepatotoxicity. Complete blood counts are recommended before and during treatment, particularly with extended courses, due to risk of bone marrow suppression. Use with caution in patients with pre-existing liver disease or impaired hepatic function. Corticosteroid therapy should be co-administered for neurocysticercosis to prevent inflammatory reactions to dying parasites. Effective contraception must be maintained during and for one month after treatment completion due to teratogenic potential.
Contraindications
Hypersensitivity to albendazole, other benzimidazoles, or any component of the formulation. Pregnancy (category C) due to demonstrated embryotoxicity and teratogenicity in animal studies. Breastfeeding should be discontinued during treatment. Not recommended for children under one year of age due to insufficient safety data. Avoid use in patients with known bone marrow suppression or pre-existing pancytopenia.
Possible side effect
Common adverse reactions include abdominal pain, nausea, vomiting, headache, dizziness, and transient liver enzyme elevations. Less frequently reported effects include leukopenia, thrombocytopenia, pancytopenia, and alopecia. In neurocysticercosis, meningeal signs, headache, hypertension, and intracranial hypertension may occur due to inflammatory response to dying parasites. Serious but rare adverse events include Stevens-Johnson syndrome, toxic epidermal necrolysis, and agranulocytosis.
Drug interaction
Cimetidine, dexamethasone, and praziquantel may increase plasma levels of albendazole sulfoxide metabolite. Inducers of cytochrome P450 enzymes such as carbamazepine, phenytoin, and rifampin may decrease albendazole concentrations. Theophylline levels may be increased when co-administered with albendazole. Concurrent use with other bone marrow suppressants may potentiate hematologic toxicity.
Missed dose
If a dose is missed, it should be taken as soon as remembered unless it is nearly time for the next scheduled dose. In that case, the missed dose should be skipped and the regular dosing schedule resumed. Double doses should not be taken to make up for a missed dose. For single-dose regimens for intestinal parasites, if vomiting occurs within 3 hours of administration, the dose should be repeated.
Overdose
Symptoms of overdose may include nausea, vomiting, abdominal cramps, diarrhea, dizziness, and headache. In massive overdose, hepatic injury and bone marrow suppression may occur. There is no specific antidote; treatment should be symptomatic and supportive. Gastric lavage may be considered if performed soon after ingestion. Hemodialysis is not likely to be effective due to high protein binding of the drug and its metabolites.
Storage
Store at controlled room temperature (20-25°C/68-77°F) in the original container. Protect from light and moisture. Keep tightly closed and out of reach of children. Do not use beyond the expiration date printed on the packaging. Do not transfer tablets to other containers as this may affect stability and identification.
Disclaimer
This information is provided for educational purposes only and does not constitute medical advice. Treatment decisions should be made by qualified healthcare professionals based on individual patient circumstances. Always follow the prescribing information provided with the medication and consult appropriate medical references for complete prescribing details.
Reviews
Clinical studies demonstrate albendazole’s efficacy with cure rates of 72-98% for ascariasis, 70-90% for hookworm, and 28-70% for trichuriasis. Systematic reviews confirm its effectiveness in mass drug administration programs for soil-transmitted helminths. In neurocysticercosis, albendazole shows superior efficacy compared to praziquantel with better cyst resolution rates. The drug is generally well-tolerated with most adverse effects being mild and transient. Long-term safety data support its use in repeated treatment cycles for chronic parasitic infections.