The combination therapy is generally used to support the management of internal parasitic burdens affecting livestock. This dual-action medicine is relevant for the management of parasitic bronchitis, parasitic gastro-enteritis, and fascioliasis in sheep.

This dual-class medicine is commonly used for the simultaneous management of infections involving both flatworms (trematodes) and various species of roundworms (nematodes). Its therapeutic benefit is relevant for addressing multiple types of infestations throughout the animal's organs and digestive tract, which supports general well-being during symptomatic phases. The medicine is considered relevant in conditions involving acute, subacute, and chronic forms of Liver Fluke infection (Fasciola species), assisting with managing the parasitic burden across all life stages. The medicine may assist with managing pronounced systemic symptoms that reflect physiological strain, such as lethargy, a state of depressed animals, and progressive weight loss.

“This approach is applicable in contexts marked by increased discomfort and functional stress associated with chronic or severe parasitic disease.”

By addressing the parasitic burden, the medicine provides supportive relief that may help ease the overall symptom load and contributes to improved comfort during periods of heightened symptoms.

---

Quick Fact: Relief for Parasitic Decline

Property	Description
Primary Indication Focus	Dual control of Trematodes (Liver Fluke) and Nematodes (Roundworms)
Symptoms Addressed	Lethargy, systemic decline, weight loss, poor grazing activity
Target Stages	Early immature, immature, and adult parasitic life stages
Key Patient Benefit	Supports improved functional stability and easing of physiological strain

Regulatory References

1. Summary of Product Characteristics from the Veterinary Medicines Directorate

The official regulatory profile for Fasinex Super (Levamisole and Triclabendazole combination) is specific to the target species, sheep, and defines eligibility based on several key constraints documented in government labeling.

Eligibility Scope

Classification	Population or Condition	Status in Regulatory Labeling
Populations Allowed	Adult sheep, young sheep (lambs), pregnant ewes, and stressed sheep.	Permitted
Populations Contraindicated	Ewes producing milk for human consumption.	Strictly Prohibited

Eligibility-Related Restrictions

Category	Specific Rule	Classification
Hypersensitivity	Animals with known hypersensitivity to the active substances or excipients.	Contraindicated
Co-treatment	Use within 14 days before or after treatment with organophosphorus compounds.	Prohibited
Milk Production	Use in ewes intended to produce milk for human consumption within one year prior to first lambing.	Prohibited

Age-related eligibility includes approval for lambs; however, certain product labels may restrict use in sheep less than seven weeks old. The medicine is approved for use in pregnant ewes but is strictly contraindicated in any ewe producing milk for human consumption, even if lactating. Eligibility status regarding specific organ dysfunction, such as hepatic or renal impairment, is not explicitly detailed in the official ovine labels.

Interactions with other medicines and products

This section outlines the officially documented interaction patterns for Fasinex Super (Levamisole/Triclabendazole), based strictly on regulatory prescribing information.

---

Interaction Scope

Property	Finding from Regulatory Documents
Medicinal product categories with documented interactions:	Medicines that are CYP2C19 substrates.
Mechanistic basis of interactions:	Inhibition of the CYP2C19 enzyme by the Triclabendazole component.
Food-related interaction constraint:	Co-administration with food is a procedural constraint, as food significantly alters systemic exposure.
Interaction-related restrictions:	No specific medicinal products are formally prohibited or contraindicated for co-administration.

---

Official Interaction Statements

Regulatory documentation defines the interaction profile through two primary pharmacokinetic (PK) domains.

• Potential for Increased Exposure of CYP2C19 Substrates: The Triclabendazole component has the documented potential to inhibit the CYP2C19 enzyme. This suggests a potential for a transient increase in plasma concentrations and total exposure of co-administered medicines that are primarily metabolized by this enzyme.
• Food-Induced Systemic Exposure Modification: Co-administration with a meal is an officially documented interaction, as pharmacokinetic studies show the Cmax and AUC (total exposure) of the Triclabendazole component are increased approximately two to three times when taken with food.

This framework highlights exposure-modifying interaction patterns, which are defined by government health authorities as the primary interaction structure.

The final mechanism-of-action text is below

Dual-Action Targeting of Parasite Neuromuscular and Cellular Systems

Fasinex Super utilizes two distinct and complementary mechanistic domains to address separate parasite classes. The first component, Levamisole, works via neuromuscular disruption, while the second component, Triclabendazole, focuses on structural and metabolic collapse. This dual strategy employs two separate mechanisms to address distinct components of the parasitic burden.

Mechanism 1: Rapid Paralysis via Receptor Agonism

The Levamisole component acts as a direct agonist on the parasite's nicotinic acetylcholine receptors (nAChR), which are necessary for normal nematode muscle function. This persistent activation leads to an uncontrolled, sustained depolarization, causing spastic paralysis of the roundworm. The resulting physiological effect is the rapid, sustained incapacitation of the parasite, leading to the parasite's inability to maintain anchorage against host gastrointestinal motility.

Mechanism 2: Cellular Failure via beta-Tubulin Inhibition

The Triclabendazole component utilizes its active metabolites to target beta-tubulin, a core structural protein in trematodes (flukes). By acting as an inhibitor of beta-tubulin polymerization, the drug prevents the assembly of microtubules, which are required for the integrity and function of parasite cells. This initiates a cascade of structural damage and metabolic collapse, leading to energy depletion and the progressive destruction of the trematode's cellular structure.

Fasinex Super is administered exclusively via the oral route as a liquid drench or suspension. The usage protocol is based on a weight-based dosing principle that involves the administration of a single, calculated volume.

Dosing is standardized around a concentration-specific rate that varies by species. The required volume is calculated from the animal’s accurate body weight to ensure delivery of 12 mg Triclabendazole and 7.5 mg Levamisole per kg (for cattle) or 10 mg Triclabendazole and 7.5 mg Levamisole per kg (for sheep).

The standard application is a single treatment event. However, the medicine may be used as part of a strategic dosing programme, and specific re-treatment intervals of approximately four to six weeks are noted for the management of acute fasciolosis. The medicine is indicated for use in young and pregnant target animals.

Procedural requirements ensure correct delivery:

Procedural Requirement	Instruction
Route of Administration	Oral drench/suspension only.
Preparation	The suspension must be thoroughly shaken prior to use.
Dosing Device	Use a calibrated dosing device; avoid underdosing.
Frequency Pattern	Single dose initially; professional guidance for repeat use.

This protocol defines the standardized approach for using the medicine.

Research evidence / Overview of studies for Fasinex Super

Evidence for Use in Fascioliasis (Liver Fluke Infection)

Research has primarily evaluated the Triclabendazole component through two main types of studies: Controlled Experimental Infection Studies and Randomized Comparative Trials conducted in field settings. These studies were designed to evaluate the medicine in sheep, cattle, and goats diagnosed with Fasciola spp. infections, specifically exploring its activity across all parasite life stages. Researchers monitored objective measurements such as the status of Faecal Egg Count Reduction (FECR) and changes in biochemical markers.

The findings describe patterns observed in the studies where the active component was applied, including measurements of fluke burden parameters in the observed populations. Evidence from these structures is associated with shifts in certain liver enzyme markers in animals with acute infection in the short term. Evidence generally reflects a research base evaluating the Triclabendazole component's activity against the target parasite.

Evidence for Use in Mixed Trematode and Nematode Infection

The research supporting the use of the dual-active combination is mainly derived from Comparative Field Trials and efficacy studies. These research structures were specifically designed to evaluate the medicine in sheep and cattle with a natural, concurrent burden of both roundworms and liver flukes. Studies simultaneously evaluated metrics for both parasite classes, including Faecal Egg Count Reduction (FECR) for roundworms and flukes, alongside physiological measures such as change in body weight (LWT) gain.

Studies reported how symptoms evolved in the observed populations, describing a simultaneous reduction in egg shedding for both parasite types following treatment with the dual-active formula. Research highlights changes measured during the study period, with some reports noted measurements of body weight gain in the observed populations over the short-term study duration. This evidence is consistent with the activity of the two component drugs against their respective target parasites when they are administered concurrently.

What Remains Uncertain About Fasinex Super Research

The scientific literature highlights what is known — and what is still uncertain — regarding this medicine. A primary limitation is that comparative evidence is lacking for a large-scale randomized trial specifically comparing the combination product versus the individual administration of the two active ingredients. The research findings may be limited by the modest sample sizes in some field studies, and the evidence quality varies across studies due to the natural variability of the field environment. Furthermore, data for certain groups remain insufficient, and research is ongoing to fully contextualize the value of the combination across all potential scenarios.

Key Studies & References

1. Summary of Product Characteristics (SPC) for Fasinex Super (VMD Reference)

Common questions about Fasinex Super (FAQ)

---

Q: How quickly should I expect Fasinex Super to start having an effect?

Official product information describes the Levamisole component’s action as causing rapid incapacitation of its target parasite. This physiological change leads to the parasite's inability to maintain anchorage.

---

Q: Does Fasinex Super cause weight gain or weight loss?

Research studies designed to evaluate the medicine report measurements of body weight gain in the observed populations over the short-term study duration. These findings are consistent with the observed improvement following the reduction of the parasitic burden in the treated subjects.

---

Q: How long does Fasinex Super stay in your system?

The active Triclabendazole component has a short elimination half-life, meaning it is processed relatively quickly by the body. Because of this, potential elevation in concentrations of co-administered medicines is described as transient (temporary) in official information.

---

Q: Why is it described that Fasinex Super affects the liver function tests?

Official reports for the active Triclabendazole component have noted transient (temporary) increases in liver enzymes and total bilirubin. These changes can be related both to the underlying parasitic infection itself, or to the processes associated with the clearance of the parasite burden.

---

Q: Is the risk of side effects higher when Fasinex Super is first started?

Adverse reactions reported for the active Triclabendazole component, such as abdominal pain and nausea, commonly begin on the day of treatment. Official information indicates these reactions typically last only a few days.

---

Q: Is Fasinex Super intended for short-term or long-term use?

Regulatory documents define the standard application as a single treatment event. However, the medicine may be used as part of a strategic dosing programme over a period of weeks, based on professional guidance related to the specific condition being managed.

---

Q: Does Fasinex Super cause changes in mood or anxiety levels?

Effects such as anxiety and irritability are noted in official reports concerning the active Levamisole component in the context of toxicosis (overexposure) in animal populations.

---

Q: Does Fasinex Super affect fertility in men or women?

The active Levamisole component has been noted in official contexts to potentially affect the ability to have children. Meanwhile, animal studies for the Triclabendazole component have not shown an increased risk of birth defects at certain doses.

---

Q: What is the best way to store Fasinex Super?

Official guidelines state the product must be stored below 30 C and be protected from frost. Guidelines indicate the product should be kept in its original container, and the regulatory shelf-life after first opening is typically set at 12 months.

---

Q: Is Fasinex Super safe for use by older adults?

Official information for the active Triclabendazole component describes its use in patients aged 6 years and older in certain contexts. Regulatory documents do not provide specific, separate details for the use of this medicine in older adults.

---

Q: Can using Fasinex Super cause lightheadedness or dizziness?

Yes, dizziness has been noted as a potential sign of Levamisole overexposure (toxicosis). Additionally, common adverse reactions reported for the active Triclabendazole component include headache and nausea.

---

Q: Are there different forms of Fasinex Super available, like a tablet versus a liquid?

According to the official regulatory labeling, Fasinex Super is administered exclusively as an oral suspension drench, which is a liquid dosage form.

---

Q: Is there a generic version of Fasinex Super available?

The active ingredient Triclabendazole has become available as a generic medicine in many countries since its patents expired. The specific brand combination, Fasinex Super, may or may not have a generic equivalent depending on the region.

---

Q: Can Fasinex Super be taken with common cold and flu medicines?

Official documents suggest the Triclabendazole component may cause a transient increase in exposure of co-administered medicines that are processed by the CYP2C19 enzyme. This enzyme metabolizes certain cold and flu treatments.

---

Q: Is Fasinex Super approved in countries outside of the United States?

The product and its variants are approved and used in numerous countries globally, including Ireland, the United Kingdom, Australia, New Zealand, and several European Union member states.

---

Q: Can Fasinex Super cause digestive issues like nausea or stomach pain?

Official documentation for the active Triclabendazole component lists common adverse reactions including abdominal pain, nausea, vomiting, and diarrhea.

Storage and Disposal Requirements

Official regulatory guidelines strictly define the conditions necessary for storing and disposing of Fasinex Super (Oral Suspension) to maintain product stability and ensure environmental safety.

Storage Conditions

Requirement	Specific Instruction
Temperature	Store below 30°C and protect from frost.
Environment	Keep the product in a cool, dry place.
Container	Store in the original container and keep it tightly closed.
Shelf-Life	Use within 12 months after first opening the immediate packaging.
Safety	The product must be kept out of the sight and reach of children.

Disposal

Unused or expired product and related waste must be disposed of in accordance with local requirements. Due to the product being dangerous to fish, it is strictly forbidden to contaminate watercourses. Empty containers must be triple or pressure rinsed before disposal to an approved waste management facility.