Antiworm

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Antiworm

Method of action: Anthelmintic

Treatment option:

Medically reviewed

Laura Arias

Last updated on 22/12/2025

This page provides general, reference-level information compiled from official medical sources. It is not a substitute for professional medical advice, diagnosis, or treatment. For decisions about your health, please consult a qualified healthcare professional.

Overview of Antiworm

Property Description
Active Ingredient Levamisole (L-Tetramisole)
Form Primarily Oral Tablets
Pharmacological Class Anthelmintic (Antinematodal Agent) and Immunomodulator
Common Use Elimination of parasitic worm infections
Origin Synthetic imidazothiazole derivative

What Type of Medicine is Antiworm (Levamisole)?

Antiworm is a pharmaceutical product containing the active substance Levamisole, which is classified primarily as a synthetic anthelmintic, or antinematodal agent. The compound is structurally recognized as a synthetic imidazothiazole derivative. Levamisole also holds a clinically recognized secondary classification as an immunomodulator, often studied for its ability to influence the function of the host's immune cells. Levamisole may restore depressed immune function of T-lymphocytes and macrophages. This dual action is a distinctive feature of the compound, differentiating it from anthelmintics that solely target parasitic structure.

What is the Composition and Form of Antiworm?

The medicine is a single active ingredient product, with its therapeutic action reliant upon Levamisole, which is the purified, pharmacologically active L-isomer of its precursor, Tetramisole. It is typically formulated as the readily water-soluble salt, Levamisole Hydrochloride. The primary physical presentation for patient use is in an oral solid form, such as tablets, designed for convenient oral administration. Levamisole maintains an established role and verified effectiveness, as indicated by its inclusion on the Model List of Essential Medicines, underscoring its general utility in addressing parasitic disease burdens.

What is the General Purpose of Antiworm?

The general purpose of Antiworm is the swift elimination of parasitic worm infections, such as those caused by roundworms. The compound achieves this by acting as a fast-acting neurotoxin on the parasite, inducing immediate and sustained spastic paralysis in susceptible organisms. This mechanism prevents the worms from clinging to the intestinal lining, facilitating their rapid, natural expulsion from the body. Beyond this core function, the drug provides the supplementary benefit of potentially helping to restore depressed immune function to a more normal state in certain clinical scenarios.

What side effects are possible with Antiworm?

Possible side effects and safety information

The official safety information for Antiworm (Levamisole) documents adverse reactions categorized by frequency and the body system affected. These classifications reflect the regulatory understanding of the medicine’s risk profile.

Documented Adverse Reactions

The most common adverse reactions listed in regulatory documents involve Gastrointestinal Disorders (including nausea, diarrhea, vomiting, and abdominal pain) and Skin and Subcutaneous Tissue Disorders (such as skin rash and urticaria).

Reactions categorized as less common or uncommon include psychiatric and nervous system effects like headache, dizziness, insomnia, and depression.

Serious Adverse Reactions

The safety profile is notable for the documented potential for rare but serious adverse reactions, particularly affecting the blood and nervous systems. These serious reactions, as defined in official regulatory texts, include:

  • Agranulocytosis: A severe and potentially life-threatening drop in specific white blood cell counts (Neutropenia).
  • Encephalopathy/Leukoencephalopathy: Severe disorders affecting the function or white matter of the brain.
  • Vasculitis: Severe inflammation of blood vessels.

Safety Considerations

Official government safety data includes specific safety considerations related to exposure. The risk of serious hematologic effects, such as agranulocytosis, is documented to increase with repeated courses of treatment or higher total doses. For pregnancy, the official labeling notes a risk of potential harm to the unborn child. Furthermore, regulatory documents specify the potential for long-term exposure to affect certain organs, including the blood system.

Overdose and Emergency Response

Overdose and When to Seek Help

An overdose of Antiworm (Levamisole) necessitates immediate medical attention or contact with emergency services, as dictated by regulatory documents. Urgent hospitalization is mandated when significant or life-threatening symptoms manifest, given the documented risks of profound CNS depression, respiratory depression, and serious cardiovascular events such as cardiac arrhythmias.

Documented Overdose Manifestations

Regulatory labeling specifies a cluster of clinical signs that may present in overdose scenarios:

  • Neurological Effects: Signs range from generalized dizziness and headache to severe neurological outcomes, including convulsions and progression toward coma.
  • Gastrointestinal and Systemic Effects: Documented systemic findings include tachycardia (rapid heart rate), paresthesia, and gastrointestinal distress such as nausea, vomiting, diarrhea, and abdominal pain.

Required Emergency Management

Management is restricted to the regulator-defined approach of symptomatic and supportive treatment, as no specific antidote is known for Levamisole. This procedure requires continuous cardiac monitoring and close observation for the manifestation of central nervous system effects. Interventions may also include gastric lavage if the overdose occurred shortly prior to clinical presentation.

Therapeutic Uses of Antiworm

What Antiworm Treats: Main Uses and Benefits

The core therapeutic utility of Antiworm (Levamisole) is centered on managing symptoms related to physical discomfort from parasitic worm infections and, in certain contexts, supporting the body's function in certain recurrent conditions. The drug is commonly used and recognized within the category of intestinal anthelmintics.


Key Therapeutic Domains

The medication is commonly used across conditions presenting with acute episodes of gastrointestinal parasitic infections, primarily involving roundworms and certain types of hookworms. These conditions generally produce symptoms related to physical discomfort such as abdominal pain, nausea, and digestive distress. The drug is relevant for easing the removal of the parasitic presence, which supports patients during episodes of heightened discomfort.

In a distinct clinical role, Antiworm is considered relevant in conditions marked by systemic or localized discomfort associated with recurrent issues. This supportive use is applied in addressing certain recurrent or episodic manifestations where additional symptomatic support is needed to help the body manage these manifestations. The general benefit may assist with symptomatic relief that helps patients cope more steadily with difficult episodes.


Quick Fact

Quick Fact: Relief for Gastrointestinal Distress

This application helps address symptom clusters related to the physical presence of intestinal parasites, providing support that helps ease the overall symptom burden in the digestive tract.

Regulatory References

  1. Electronic Essential Medicines List of the World Health Organization (WHO)

Eligibility and Restrictions for Use

Who Can and Cannot Use Antiworm?

Eligibility for Antiworm (Levamisole) is strictly defined by regulatory documents, focusing on patient history, physiological state, and potential substance interactions.


Official Regulatory Eligibility Status

Status Population or Condition
Contraindicated Patients with known hypersensitivity to the drug or a history of blood disorders (e.g., agranulocytosis). Prohibited for use within 14 days of administering organophosphorus compounds.
Not Recommended Breastfeeding mothers, based on authoritative health recommendations (WHO). Pregnant women, unless conditional use criteria are met (benefits must outweigh risks).
Requires Caution Patients with pre-existing hepatic impairment (liver function issues). Conditional use may be required for those with comorbidities like epilepsy or existing infection.
Use Established Adults and Children (for anthelmintic indications). Older adults are generally permitted, though specific comparative safety data may be limited in labeling.

Eligibility Classification Summary

Eligibility is defined by absolute contraindications and conditional use requirements. The drug was formerly assigned FDA Pregnancy Category C, establishing that use during pregnancy is restricted to cases where potential benefit justifies the risk.

What should I know about interactions with other medicines?

Interactions between Antiworm medications (such as albendazole and mebendazole) and other products can alter the efficacy or safety of the treatment. It is crucial to inform your healthcare provider about all prescription drugs, over-the-counter medicines, vitamins, and herbal supplements you are taking.

Key Drug Interactions

Certain medicines can affect the concentration of antiworm drugs in the body, potentially reducing effectiveness or increasing side effects. Conversely, antiworm medication can also influence the levels of other co-administered drugs.

Interacting Drug Class/Example Effect on Antiworm Drug Potential Risk
Cimetidine (for stomach acid) May increase antiworm concentration Increased side effects
Metronidazole (an antibiotic) Increased risk of severe skin reactions (e.g., Stevens-Johnson syndrome), particularly with mebendazole
Anticonvulsants (e.g., Carbamazepine, Phenytoin) May decrease antiworm concentration Reduced antiworm effectiveness
Dexamethasone (a steroid) May increase albendazole concentration Increased side effects

Food and Herbal Interactions

  • Fatty Foods: Taking albendazole with a high-fat meal can significantly increase its absorption, which is often desirable for treating certain tissue infections but may lead to increased side effects. Follow your doctor's dosing instructions precisely.
  • Grapefruit Juice: May increase the concentration of albendazole in the body.
  • Herbal Remedies and Supplements: Due to lack of extensive testing, the effects of many herbal products on antiworm medications are unknown. Caution is advised.

Mechanism of Action

Mechanism: Parasite Neuromuscular Blockade

This mechanism directly targets the parasite's nicotinic acetylcholine receptors (nAChRs) within the neuromuscular system. By acting as an agonist, Levamisole causes the receptor channels to remain persistently open, resulting in continuous stimulation and subsequent membrane depolarization. This molecular action translates into the physiological consequence of irreversible spastic paralysis, which prevents the worm from maintaining muscle control or clinging to the intestinal wall, thus facilitating its physical clearance from the gastrointestinal tract via natural peristalsis.


Mechanism: Restoration of Suppressed Immune Cell Function

Levamisole also engages in a secondary immunomodulatory mechanism by influencing the activity of key host immune cells, specifically T-lymphocytes and macrophages. This is achieved by affecting intracellular signaling pathways like cAMP. The mechanism influences the activity of key host immune cells; this action is observed when cell-mediated immunity is suppressed, contributing to the adjustment of cellular activity toward baseline levels.

Dosage and Administration Information

The medicine Antiworm (Levamisole) is administered strictly via the oral route, available primarily in the form of tablets or an oral solution. The usage protocol is characterized by two distinct procedural structures: a short-term, acute regimen and a long-term, intermittent cyclic regimen, depending on the clinical context.

For the acute anthelmintic use, the protocol mandates a single administration of the medicine. The standard dose for both adult and pediatric patients is often determined by body weight, calculated in the range of 2.5 to 3 mg per kilogram of body weight, or as a single fixed dose for adults. This acute administration is usually taken by mouth after a light meal.

In contrast, the supportive use (historically for certain adjuvant regimens) follows a more complex, long-term, cyclic schedule. This structure involves administering a fixed dose, such as 50 mg, three times daily for three consecutive days. This three-day course is then repeated at specific intervals, often every two weeks, and may be continued for up to one year, establishing a predefined duration pattern.

Regarding adherence to the schedule, official instructions for all regimens specify that if a scheduled administration is missed, the patient must skip the missed dose and not attempt to double the dose at the next scheduled time. The medicine is not to be used in any other manner than described in its regulatory labeling.

Recent Clinical Evidence

Antiworm: Recent Clinical Evidence

Recent clinical research concerning antiworm medications, particularly benzimidazoles (like mebendazole and albendazole) and macrocyclic lactones (like ivermectin), has focused on assessing their effectiveness against soil-transmitted helminth (STH) infections, which include hookworm, roundworm (Ascaris lumbricoides), and whipworm (Trichuris trichiura).


Efficacy Against Specific Nematodes

Studies comparing different antiworm agents have shown varying degrees of efficacy depending on the parasite species. Measures of success generally rely on the Cure Rate (CR)—the percentage of participants whose stool samples become egg-negative after treatment—and the Egg Reduction Rate (ERR).

Parasite Species Typical Efficacy Observation
Roundworm (A. lumbricoides) Single-dose treatment with mebendazole or albendazole has frequently demonstrated high cure rates in clinical trials.
Hookworm (e.g., N. americanus) Efficacy may be lower and more variable compared to roundworm. Multi-dose regimens have been explored in research to assess potential improvements over single doses.
Whipworm (T. trichiura) This species is often the most challenging to treat with single-dose regimens, with observed cure rates generally lower than for the other common STHs.

Fixed-Dose Combination Research

Research has investigated the use of fixed-dose combinations of two different antiworm drugs, such as ivermectin and albendazole. Trials have evaluated whether co-administration or fixed combinations of these agents demonstrate improved effectiveness against certain parasite species, particularly for mass drug administration programs.


Resistance Monitoring

Given the widespread use of benzimidazoles in public health programs, ongoing global surveillance studies are essential to monitor for any changes in drug effectiveness. This monitoring is critical for detecting the potential emergence of anthelmintic resistance that could affect future treatment guidelines.

Frequently Asked Questions (FAQ)

Common questions about Antiworm (FAQ)

Q: Does Antiworm work right away?

A: Official information describes Antiworm as being rapidly absorbed after it is taken by mouth, with peak concentrations typically reached within 1 to 4 hours. This profile is consistent with the regulatory description of its effect as a fast-acting neurotoxin on the target organism.

Q: How long does Antiworm stay in your system?

A: Studies examining the active substance in Antiworm (Levamisole) report that the plasma concentration of the active substance typically reduces by half within about 4 hours. However, traces of the total active material may remain detectable for a longer duration.

Q: Can Antiworm be used for preventing the condition?

A: Antiworm is officially indicated for the treatment of parasitic infections. Its approved regulatory labeling defines its role for the treatment of diagnosed parasitic infections.

Q: Is Antiworm the same as [Similar Drug Name]?

A: Antiworm's active ingredient is Levamisole, which is chemically classified as a synthetic imidazothiazole derivative. This makes it distinct from other antiworm agents, such as the benzimidazoles (like mebendazole or albendazole), which have different chemical structures and primary mechanisms of action.

Q: What is the difference between Antiworm and over-the-counter worm medicines?

A: The active substance in Antiworm is included on the World Health Organization's Model List of Essential Medicines for its established role. Regulatory information indicates it is typically associated with prescription-level controls due to its documented safety profile, including the potential for rare, serious blood disorders requiring professional oversight.

Q: Do I need to change my diet while taking Antiworm?

A: Official documents generally suggest that Antiworm does not require a specific diet during treatment. However, the regulatory instructions for the acute regimen often specify that the dose should be taken by mouth after a light meal.

Q: Can Antiworm cause long-term side effects?

A: Regulatory safety documents note that the potential for certain serious adverse reactions, such as severe blood disorders like agranulocytosis, is documented to increase when the drug is taken in repeated courses or in higher total doses.

Q: What happens if I miss a dose of Antiworm? (General information/clarification)

A: The general principle described in regulatory instructions for a missed dose is that the patient must skip the missed dose and not attempt to double the dose at the next scheduled time. Official regulatory instructions specify that the missed dose should be skipped to maintain the integrity of the prescribed treatment regimen.

Q: Is it common to feel tired after taking Antiworm?

A: Based on regulatory data and clinical experience, fatigue, or general tiredness, has been reported among the less common adverse reactions observed in individuals receiving Antiworm.

Q: Does Antiworm interact with common supplements like multivitamins?

A: Official documents provide detailed interaction information for specific prescription drugs. While specific interactions with standard multivitamins are generally not detailed, regulatory texts advise general caution regarding co-administration of supplements. Therefore, standard medical consultation procedures are recommended before co-administration.

Q: Is it possible to take Antiworm if I am currently taking medication for high blood pressure?

A: Official documents list known, specific drug interactions but generally do not list a contraindication for use with broad drug classes like general antihypertensive (high blood pressure) medications. Due to the complexity of potential interactions, it is recommended that the patient follows standard medical consultation procedures before co-administration.

Q: Can a history of seizures affect eligibility for Antiworm?

A: Official regulatory documents indicate that patients with pre-existing conditions like epilepsy, which is associated with seizures, require caution and conditional use. This means use may be restricted or require close professional monitoring.

Q: Is it important to complete the full course of Antiworm treatment?

A: The full course of Antiworm is defined by precise, multi-cycle regimens in regulatory guidelines. Public health and treatment guidelines emphasize the role of adherence and completing the prescribed regimen to ensure adherence to the prescribed regimen, which is important for maximizing expected efficacy and aligning with public health goals for resistance management.

Q: How is the safety of Antiworm monitored after it is approved?

A: The safety of Antiworm is continuously monitored through established post-marketing surveillance systems. These systems, run by national regulatory agencies, collect and analyze reports of adverse reactions to detect new or changing safety concerns as the medicine is used more widely.

Q: What happens if I feel like Antiworm is not working?

A: Research evidence indicates that treatment success (efficacy) can vary depending on the exact parasite species being treated. Official guidance focuses on the importance of monitoring treatment success following administration, often confirmed through follow-up laboratory testing.

Q: Is there a possibility of becoming resistant to Antiworm over time?

A: Global surveillance studies by public health bodies are continuously conducted to monitor for any changes in the effectiveness of antiworm drugs. This monitoring is critical for detecting the potential emergence of anthelmintic resistance that could affect future treatment guidelines.

Q: Does the time of day matter when taking Antiworm?

A: Yes, official instructions address the timing. The acute regimen is specified to be taken by mouth after a light meal. Additionally, the long-term cyclic regimen requires a fixed dose to be taken three times daily, suggesting specific timing throughout the day is a condition of use.

Q: Can Antiworm affect the results of other medical tests?

A: Regulatory precautions recommend regular monitoring of hematologic (blood) parameters due to the potential for serious blood disorders, such as agranulocytosis. This indicates that the medicine has the potential to influence these specific test results, requiring professional supervision as detailed in the regulatory precautions.

Q: Are there any known interactions between Antiworm and alcohol consumption?

A: Official regulatory texts advise that consumption of alcohol is not recommended while receiving Antiworm due to the potential to increase the risk of certain adverse effects, such as severe headaches and dizziness.

Q: Can people with kidney problems use Antiworm?

A: Regulatory guidance indicates that Antiworm is generally not recommended for use in patients with severe kidney diseases (renal impairment). This restriction is based on the potential for an increased risk of serious adverse effects in this population.

Q: What is the typical timeframe for a follow-up after Antiworm treatment?

A: While the exact time frame can vary based on the clinical situation, the long-term cyclic regimen protocols often involve repeat courses at specified intervals, such as every two weeks. This defined structure suggests that follow-up and monitoring are required on a defined, systematic schedule.

Q: Does Antiworm need to be taken with food?

A: The official instruction for the acute anthelmintic use specifies that the dose is typically taken by mouth after a light meal. The instruction to take the dose after a light meal indicates that administration with food is a condition of use related to absorption and tolerability for the acute regimen.

Q: Why is Antiworm sometimes used for conditions other than worm infections?

A: Antiworm (Levamisole) has a clinically recognized secondary classification as an immunomodulator. It has been studied for its ability to influence the function of host immune cells, which forms the basis for its investigation and historical use in non-anthelmintic (non-worm) scenarios.

Q: Why do official documents mention potential vision changes with Antiworm?

A: Official safety data documents that adverse reactions observed during clinical experience include ocular (eye-related) side effects, such as the potential for blurred vision. This is a recognized adverse reaction that is monitored during treatment.

Q: Are there different brand names for the medication Antiworm?

A: The active substance in Antiworm is Levamisole. Like many established pharmaceuticals, this substance has been marketed under various trade names globally by different companies, depending on the country and the time of regulatory approval.

Q: Does Antiworm have any sedative effects or cause drowsiness?

A: The official safety profile for Antiworm lists adverse reactions affecting the nervous system. These documented effects include both dizziness and somnolence, which is a medical term for drowsiness.

Q: What is the official recommended age limit for Antiworm use?

A: While the drug is generally established for use in 'Adults and Children' for anthelmintic indications, some specific clinical guidelines and protocols may specify a minimum age, such as not less than two years, depending on the particular condition being treated.

Q: Is there a maximum time a person can be treated with Antiworm?

A: For the long-term cyclic regimen, regulatory protocols define a treatment duration pattern that may be continued for up to one year. This established duration sets a maximum time frame for use within that specific clinical context.

Q: Where can I find the official prescribing information for Antiworm?

A: The official prescribing and regulatory information is available through the databases and websites of national drug authorities. Examples include the FDA’s DailyMed or the EMA’s Summary of Product Characteristics (SmPC).

Q: Can Antiworm cause issues with liver function tests?

A: Official safety documents list hepatic impairment (liver function issues) as a condition requiring caution. Additionally, rare instances of elevated serum creatinine and increased alkaline phosphatase—markers monitored in liver function tests—have been reported in adverse reaction databases.

How should Antiworm be stored and disposed of?

How to Store and Dispose of Antiworm

Storage and disposal of Antiworm (Levamisole) must strictly adhere to regulatory labeling to maintain product stability and safety.

Official Storage Conditions

Antiworm must be stored at a temperature below 30°C (86°F) in a dry place and protected from direct sunlight. The product must not be frozen. For stability, the container must be kept closed when not in use. A mandatory requirement is to keep all medicines out of the sight and reach of children.

Disposal Instructions

Disposal of unused or expired Antiworm must be in accordance with particular national regulations. This medication should not be flushed down the toilet or poured into a drain, as it is not on the FDA's flush list. Instead, the disposal process must avoid release to the environment, often utilizing community drug take-back programs or discarding through an approved waste disposal plant.

Attention! Always consult to a doctor or pharmacist before using pills or medicines.

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