What Is Triclabendazole?

Triclabendazole is an anthelmintic (anti-worm) drug in the benzimidazole family, but it’s special because – unlike many other benzimidazoles – it’s highly active against trematodes (flukes) such as Fasciola spp. It’s the drug of choice for liver fluke infections and the only medicine currently recommended by the World Health Organization (WHO) for human fascioliasis.

Mechanistically, Triclabendazole Tablet is absorbed orally and converted into active metabolites that interfere with the parasite’s microtubule formation and cellular metabolism, damaging the tegument (outer surface) and internal organs of the flukes, ultimately killing them.

How Effective Is It in Humans?

Clinical Cure Rates

In multiple human studies, triclabendazole has shown high efficacy:

In a trial of 70 patients treated with 12 mg/kg per day for 2 days, stool tests were negative for fluke eggs in ~83% after one cycle, with additional cures after second/third cycles.

A study in Cuba found that using 20 mg/kg (two 10 mg/kg doses) resulted in a ~92% parasitological cure rate, with most abnormalities on imaging and stool testing resolving after therapy.

Patients in Northern Vietnam treated with a single larger dose (20 mg/kg) also had high cure rates, and failures often required repeat dosing.

These results explain why triclabendazole stands apart from other worm medicines like albendazole or praziquantel, which are far less effective or ineffective against Fasciola. Buy Triclabendazole Online at top pharmacy Medzsupplier.

Dosing & Administration

For humans, the standard regimen is typically 10 mg/kg orally, repeated after ~12 hours, taken with food to enhance absorption. This relatively short course is convenient and well tolerated in most people.

How Effective Is It in Animals?

Much of the strongest data we have comes from veterinary use, where fasciolosis has a major economic impact:

Classic veterinary research in calves showed 100% reduction in F. hepatica burden after triclabendazole at 6–12 mg/kg doses compared to untreated animals.

Large field trials in sheep and cattle, including combinations with other agents like ivermectin, found >98% efficacy against liver fluke infections when measured by reduction in egg counts and parasite load.

Combined treatments often perform very well, with one study showing combined triclabendazole/ivermectin reducing more eggs than triclabendazole alone.

These veterinary outcomes underscore how potent triclabendazole is when flukes are susceptible to it.

Challenges: Resistance and Treatment Failures

While triclabendazole is widely effective, efficacy is not uniform everywhere:

Emerging Resistance

Resistance has been documented especially in livestock populations where triclabendazole has been overused for decades. Parasites that survive treatment multiply and spread, making future treatments less reliable.

In human populations in Peru and other endemic areas, researchers have observed declining cure rates with repeated triclabendazole courses (e.g., ~55% cure after first dose and decreasing with subsequent treatments).

Resistance in animals can stem from under-dosing, frequent use, or poor timing (treating when flukes are not in susceptible stages).

So while many populations still respond well, regions with intensive use of triclabendazole face real concerns about reduced efficacy.

Other Reported Treatment Issues

Some recent studies in human and animal settings have shown modest cure rates or incomplete responses with triclabendazole alone, suggesting that:

Flukes at certain life stages may be less susceptible

Mixed infections can complicate results

Combined therapies may be more effective in some contexts

In these cases, treatment can be repeated or supplemented with other drugs and close follow-up testing is recommended.

Is Triclabendazole Still the “Best”?

Yes — in most cases, triclabendazole remains the most effective and preferred treatment for fascioliasis in humans and livestock today.

Strengths:

Works against both early immature and adult flukes

High cure rates in many settings

Short treatment course

Generally safe and well tolerated

Limitations:

Resistance is an increasing problem in both animals and humans

Cure rates vary by region and parasite strain

Repeat treatment or combination strategies may be needed in resistant populations