PH8.9 | PH8.9 | Anthelmintic Drugs — SDL Guide — Summary & Reflection

KEY TAKEAWAYS

Benzimidazoles (albendazole/mebendazole): β-tubulin inhibition → microtubule disruption → impaired glucose uptake → worm starvation. Albendazole 400mg single dose = first-line for most intestinal roundworms (Ascaris, hookworm, Enterobius, Trichuris). Teratogenic — avoid in first trimester (use pyrantel or mebendazole in pregnancy). Mebendazole poorly absorbed (gut only). Albendazole absorbed (systemic) — use for hydatid and neurocysticercosis (with steroids).

Pyrantel pamoate: nicotinic cholinomimetic → spastic paralysis → expulsion. Ascaris, hookworm, Enterobius. Safe in pregnancy (not absorbed). NOT for Trichuris. Antagonistic to piperazine.

Ivermectin: glutamate-gated Cl⁻ channel → hyperpolarisation → flaccid paralysis. First-line for Strongyloides (cure rate superior to albendazole); filariae; scabies. Avoid in pregnancy. Mazzotti reaction in filarial patients.

Praziquantel: Ca²⁺ permeability → tegument disruption → immune-mediated death. Drug of choice for schistosomiasis, taeniasis, neurocysticercosis (combine with dexamethasone + antiepileptics), liver flukes (NOT Fasciola — use triclabendazole).

Niclosamide: uncouples oxidative phosphorylation in tapeworm; intestinal tapeworm only (not absorbed → no CNS activity; not for neurocysticercosis).

Fasciola trap: praziquantel NOT effective vs Fasciola hepatica — use triclabendazole.

REFLECT

India's National Deworming Day (NDD) administers albendazole to approximately 200 million preschool and school-age children annually. Evidence shows this reduces worm burden, anaemia, and stunting. However, some researchers argue that MDA without sanitation improvements simply leads to rapid reinfection — 'deworming without water and sanitation is like mopping the floor without turning off the tap.' As a future clinician and public health advocate, how would you balance the pharmacological benefits of albendazole MDA with the structural interventions (WASH — Water, Sanitation, Hygiene) needed for sustained helminth control?