ZENTEL TABLETS

Indications

• Neurocysticercosis
• Hydatid disease (Echinococcosis)
• Giardiasis
• Ascariasis
• Enterobiasis (pinworm infection)
• Hookworm infection
• Strongyloidiasis

Dosage

Children: Pediatric dosing of albendazole should be determined based on the specific condition and child’s weight. Refer to the BNF for Children for appropriate dosing guidelines.

Adults: The adult dosage of albendazole varies based on the condition being treated. For neurocysticercosis, the usual dosage is 15 mg/kg daily divided into two doses for 8 to 30 days. For other conditions, refer to specific treatment guidelines.

Mechanism of action

Albendazole acts by inhibiting the polymerization of tubulin into microtubules, which is essential for cellular processes such as division and energy metabolism. This disruption leads to impaired glucose uptake by the parasites, resulting in their depletion of energy stores and eventual death.

Pharmacodynamics

Albendazole has a broad spectrum of activity against various helminths. Its efficacy is attributed to its ability to disrupt the microtubule function in parasites, which is vital for their growth and reproduction. The drug demonstrates concentration-dependent killing, meaning that higher concentrations lead to increased efficacy against the parasites.

Pharmacokinetics

Albendazole is poorly absorbed from the gastrointestinal tract, with bioavailability significantly enhanced when taken with fatty meals. It is metabolized in the liver to its active metabolite, albendazole sulfoxide, which has a longer half-life and is responsible for the drug's anthelmintic activity. The drug is primarily excreted in the urine as metabolites, and its elimination half-life is approximately 8 to 12 hours.

Contra-indications

• Hypersensitivity to albendazole or any of its components
• Severe liver disease
• Pregnancy (especially during the first trimester)

Adverse effects

• Headache
• Nausea
• Vomiting
• Abdominal pain
• Dizziness
• Liver enzyme elevation
• Rarely, bone marrow suppression

Interactions

• Cimetidine may increase albendazole levels
• Rifampin may decrease albendazole levels
• Antiepileptic drugs (e.g., phenytoin, carbamazepine) may reduce albendazole efficacy

Precautions

• Monitor liver function during treatment, particularly in patients with pre-existing liver disease
• Use caution in patients with a history of bone marrow suppression
• Not recommended for use in children under the age of 2 without specialist advice

Pregnancy

Albendazole is contraindicated during pregnancy, particularly in the first trimester, due to potential teratogenic effects.

Breast-feeding

Caution is advised when using albendazole during breastfeeding; it is recommended to either avoid breastfeeding or discontinue the drug based on clinical judgement.

Storage

Store at room temperature, away from moisture and heat. Keep out of reach of children.

Formulations

• Tablets (400 mg)
• Suspension (200 mg/5 mL)