Anthel

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Anthel

Method of action: Anthelmintic

Treatment option: Enterobiasis

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 Anthel

What is Anthel? Identity, Classification, and Purpose

Property Description
Active ingredient Pyrantel (commonly as Pamoate)
Form Oral suspension, tablets, chewable tablets
Pharmacological class Anthelmintic agent
General purpose Elimination of intestinal parasitic worms (nematodes)
Origin Synthetic pyrimidine derivative

What is Anthel and Its Pharmacological Identity?

Anthel is a medicine defined by its active ingredient, Pyrantel, a synthetic compound most commonly administered as the Pyrantel pamoate salt in human treatments. It is formally classified as an anthelmintic agent—the high-level pharmacological class for drugs used to treat parasitic worm infections—and belongs to the more specific class of tetrahydropyrimidine derivatives. Pyrantel is a recognized treatment option with an established role in global medicine.

Anthel's Available Forms and Preparation

Pyrantel is prepared for oral administration and is typically available in several dosage forms, including oral suspension and various tablets, such as chewable tablets. The development of Pyrantel in these forms is often geared toward patient convenience, allowing flexibility for different patient groups. The choice of the pamoate salt form is key because its low solubility ensures the drug is poorly absorbed from the gastrointestinal tract. This property means the medicine is intended to act directly where the parasites reside, limiting systemic exposure.

What is the General Purpose of Anthelmintic Agents Like Pyrantel?

The primary purpose of Anthel is the reliable elimination of specific intestinal parasitic worm infections, particularly those caused by susceptible nematodes like roundworms and pinworms. This objective is achieved by the drug's action as a depolarizing neuromuscular blocking agent against the parasites. This mechanism causes spastic paralysis in susceptible worms, which leads them to detach from the intestinal wall. This facilitates their natural, passive expulsion from the body via the host's normal digestive processes, fulfilling the medicine's general therapeutic goal.

Regulatory References

  1. NIH DailyMed Label for Pyrantel Pamoate
  2. Pyrantel Pamoate Label on DailyMed (NIH/NLM)
  3. NIH LiverTox Documentation

What side effects are possible with Anthel?

Possible Side Effects and Safety Information

The safety profile of Anthel (Pyrantel Pamoate) is structured by governmental regulatory authorities (such as the FDA and EMA) based on documented adverse reactions and specific usage restrictions.

Adverse Reaction Scope

Classification Affected Systems and Reactions Notes
Common Effects Gastrointestinal Disorders: Nausea, vomiting, diarrhea, and abdominal cramps. Nervous System Disorders: Headache, dizziness, and drowsiness. These effects are generally mild and transient, as noted in official labeling.
Rare/Post-Marketing Hepato-biliary Disorders: Elevated liver enzyme levels. Skin Disorders: Rash. These events are reported less frequently or through post-marketing surveillance.

Regulatory Safety Restrictions and Cautions

Regulatory documents outline specific circumstances requiring caution or contraindication to ensure safe use:

  • Contraindication: Use is formally prohibited in individuals with known hypersensitivity to Pyrantel or any other component of the formulation.
  • Population-Specific Caution: Specific caution is required for patients with pre-existing liver disease or severe hepatic impairment.
  • Drug-Related Restriction: Concomitant use with Piperazine (another anthelmintic) is officially restricted due to potential antagonistic effects that could compromise the intended therapeutic action.

Regulatory Safety Summary

The official safety information structures the understanding of Anthel's risks by establishing that the most frequently encountered adverse reactions are mild and transient, primarily affecting the gastrointestinal and nervous systems. This profile is balanced by specific, non-negotiable limitations (contraindication) and targeted safety requirements (caution in hepatic impairment), which collectively define the boundaries of regulated use.

Overdose and Emergency Response

Overdose Map: Overdose and when to seek help — Official Regulatory Information for Anthel

The following structure is derived strictly from the official overdose sections of government regulatory documents for Anthel (Pyrantel Pamoate).

Overdose Scope

Domain Official Regulatory Statement
Documented overdose presentations Overdose may present with gastrointestinal disturbance, superficial skin reactions, and central nervous system effects.
Physiological systems affected (as stated in label) Gastrointestinal system, Skin, and Central Nervous System.
Dose-related or exposure-related factors (if applicable) The profile relates to acute accidental overdose situations.
Population-specific overdose notes (if applicable) No specific population-based considerations (e.g., pediatric or geriatric) are documented in the overdose section.
Emergency-response statements (as written in official documents) Seek professional assistance or get medical help.
When immediate medical help is required (label-derived phrasing only) Contact a Poison Control Center immediately (or "right away").

Overdose Classifications (High-Level)

Classification Official Regulatory Statement
Severity classification (as defined in official documents) Overdose manifestations include effects on the Central Nervous System.
Regulatory basis (EMA / FDA / etc.) FDA / DailyMed Prescribing Information (Overdose Section).
Overdose-context constraints (as defined in official documents) Management is based on providing symptomatic and supportive treatment.

Resulting Overdose Structure

Official overdose statements:

  • Accidental overdose may result in documented clinical manifestations, including gastrointestinal disturbance, superficial skin reactions, and central nervous system effects.
  • In the event of an overdose, the regulatory documents mandate that the individual seek professional assistance and contact a Poison Control Center immediately.
  • The documented management strategy for Pyrantel Pamoate overdose is symptomatic and supportive treatment, with no specific antidote listed in the official labeling.
  • Procedural guidance states that inducing vomiting should not be done unless directed by medical personnel.

Connection to the Overall Overdose Profile

Government regulatory documents define the overdose profile by listing the expected symptom clusters—gastrointestinal, skin, and neurological effects—which determine the level of concern. The regulatory structure mandates that these manifestations trigger an immediate and non-negotiable emergency action to seek professional assistance and contact a Poison Control Center. The official management strategy is defined as symptomatic and supportive treatment, guiding the necessary clinical response.

Therapeutic Uses of Anthel

What Anthel Treats: Main Uses and Benefits

The therapeutic role of Anthel (Pyrantel Pamoate) focuses on the effective management of specific intestinal parasitic infections and is relevant for easing the associated distressing symptoms. The medicine is commonly used for infections caused by pinworms and roundworms.

Anthel is primarily applied across conditions presenting with systemic or localized discomfort caused by parasitic worms, mainly targeting pinworm (Enterobius vermicularis) and roundworm (Ascaris lumbricoides). The medicine helps address symptom clusters that create noticeable physiological strain, particularly the symptoms that interfere with daily functioning, such as the often nocturnal anal itching, abdominal cramping, and general gastrointestinal distress.

“Anthel is commonly used when short-term symptomatic assistance is needed in contexts involving acute or disruptive symptom patterns, such as severe itching.”

By easing these underlying irritative states, the medicine contributes to improved comfort during symptomatic periods and assists with maintaining functional stability by helping to ease sleep-interfering symptoms. It is often used to treat eligible family members of an infected individual simultaneously, which supports the overall effort to reduce the potential for reinfection in close living environments.

Quick Fact: Relief for Nocturnal Pruritus The most immediate patient benefit often relates to the easing of difficult night-time itching, which supports the patient during difficult episodes by easing distress and contributes to improved comfort and rest.

Regulatory References

  1. NIH LiverTox Documentation on Pyrantel

Eligibility and Restrictions for Use

Official Population Eligibility for Anthel (Pyrantel Pamoate)

Regulatory authorities define who may use Anthel under standard labeled conditions and which populations require professional consultation or are formally contraindicated. Eligibility is primarily determined by age, weight, and the presence of certain medical conditions.

Category Regulatory Status Status Notes (Based on Labeling)
General Eligibility Permitted Adults and children two years of age and older who meet the minimum weight requirements.
Absolute Contraindications Prohibited Patients with known hypersensitivity or allergy to Pyrantel Pamoate or any other ingredient in the formulation.
Age/Weight Restrictions Restricted/Not Recommended Children under two years of age or weighing less than 25 pounds (11 kg); use is not recommended unless directed by a doctor.
Pre-existing Conditions Conditional Use Individuals with liver disease must not take the product unless directed by a doctor. Cautions are also noted for patients with severe malnutrition or anemia.
Pregnancy and Lactation Conditional Use Pregnant individuals must not take this product unless directed by a doctor. For breastfeeding women, safety has not been established, requiring professional guidance.

This structure reflects the mandated eligibility requirements for Anthel, focusing strictly on who can or cannot use the medicine according to governmental regulatory documents.

What should I know about interactions with other medicines?

The official regulatory interaction profile for Anthel (albendazole) details pharmacokinetic (PK) and pharmacodynamic (PD) effects resulting from co-administration with other substances.

Exposure-Modifying Substances

Certain medicinal products are documented to significantly alter the plasma concentration of Anthel’s active metabolite, albendazole sulfoxide.

Interaction Type Examples of Interacting Substances/Classes
Increased Drug Exposure Dexamethasone, Praziquantel, Cimetidine
Decreased Drug Exposure Anticonvulsants (e.g., Phenytoin, Fosphenytoin)

Coadministration with Dexamethasone increases the steady-state trough concentrations of the active metabolite by approximately 56%, while Praziquantel increases mean maximum concentration and Area Under the Curve (AUC) by about 50%. Conversely, enzyme-inducing anticonvulsants decrease the active metabolite’s levels, which may reduce efficacy. Additionally, Anthel induces Cytochrome P450 1A, which may necessitate plasma concentration monitoring for sensitive substrates like Theophylline.

Other Constraints

The label indicates a risk of additive myelosuppression when Anthel is coadministered with other agents that cause bone marrow suppression. Furthermore, consumption of grapefruit products should be avoided due to the potential for increased drug levels via inhibition of CYP3A4 metabolism.

Food: Administration with meals, particularly those containing fat, is stated as mandatory to significantly enhance the absorption of the active metabolite. Population-specific monitoring is required for patients with hepatic disease, as they are at an increased risk for bone marrow suppression when treated with Anthel.

Mechanism of Action

The mechanism of action of Pyrantel (Anthel) begins with its function as a selective agonist at a specific L-subtype of Nicotinic Acetylcholine Receptors (nAChRs), which are expressed on the somatic muscle cells of susceptible nematodes. This interaction causes a sustained, forceful activation of the worm's neuromuscular system, mimicking and exceeding the effect of the endogenous neurotransmitter. The continuous signaling leads to an irreversible depolarization of the muscle cell membrane, establishing a depolarizing neuromuscular blockade. This cascade rapidly culminates in spastic paralysis (tetany)—a state of severe, uncontrolled muscular contraction. Physiologically, this paralysis causes the worm to lose its ability to move or maintain adherence to the host's intestinal lining. The overall effect is further constrained by the drug's formulation as the poorly absorbed pamoate salt, which limits its mechanism of action almost exclusively to the intestinal lumen, making it unable to exert its effect on migratory larval stages in host tissues or on species lacking the targeted nAChR subtype.

Dosage and Administration Information

How Anthel (Pyrantel Pamoate) Is Used

Anthel is intended for use as a short-term, acute course for the elimination of specific intestinal parasites, following standard administration parameters.


Official Administration Guidelines

Instruction Category Official Guideline
Route of Administration The approved method is oral intake.
Dosing Schedule A single dose is calculated as 11 mg Pyrantel base per kilogram of patient body weight (or 5 mg/lb), with a maximum permitted dose of 1 gram Pyrantel base.
Timing in Relation to Meals Administration is flexible and can occur with or without food and at any time of day.
Preparation Requirements Oral suspension must be shaken well before use and the dose must be measured precisely using a calibrated device.

Usage Structure and Conditions

Age-Group Administration Rules:

Anthel is not intended for use in children under two years of age or those weighing less than 25 pounds, unless specifically directed by a healthcare professional. Caution is also advised regarding the regimen for patients with pre-existing hepatic impairment.

Repetition and Procedural Conditions:

The initial treatment is a single course. A single repeat dose may be administered two to three weeks (14 to 21 days) later, but only if symptoms persist or if re-exposure is confirmed. It is explicitly stated that no laxative is required for use. The overall administration often involves the simultaneous treatment of all eligible family members in the household environment as a procedural measure.

Recent Clinical Evidence

Research Evidence / Overview of Studies for Anthel

The evidence base for Anthel (Pyrantel Pamoate) primarily comes from clinical studies like Randomized Controlled Trials (RCTs) and subsequent large-scale systematic reviews. This body of research was conducted to explore patterns of helminth egg or worm detection and infection recurrence across different indications.


Evidence for Use in Pinworm Infection ( extitEnterobius vermicularis)

Research exploring pinworm infection, or enterobiasis, typically involves short-term RCTs and clinical trials. These studies were designed to monitor outcomes related to the detection of helminth eggs or worms following administration, particularly the Parasitological Cure Rate, which measures the non-detection of eggs or worms, often using the perianal swab or Scotch tape test.

Studies monitored how patient-reported outcomes related to discomfort evolved in the observed populations, and findings describe patterns observed in the studies that were later included in major public health guidelines. A common pattern in pinworm research is the use of a two-week follow-up interval following the initial administration, which established the need for a second assessment point in the research. Long-term outcomes are not well characterized, as research primarily focuses on short-term non-detection needed to confirm the initial outcome.

Evidence for Use in Roundworm Infection ( extitAscaris lumbricoides)

The evidence for roundworm infection (ascariasis) was primarily evaluated through RCTs and large systematic reviews that often included Anthel alongside various comparators. Studies explored outcomes related to physical discomfort and outcomes reflecting daily functioning or activity level by monitoring the Parasitological Cure Rate and the Egg Reduction Rate (ERR). Findings describe consistent patterns related to Parasitological Cure Rate measurements in studies involving school-aged children and adults in endemic areas. The reported outcomes were generally focused on the intermediate-term non-detection of the parasite, typically 2 to 4 weeks post-administration.

What is Still Uncertain About Anthel's Research Record

The evidence highlights what is known — and what is still uncertain about Anthel. A key limitation across the research is the pattern of subsequent evaluation at two weeks for pinworm infection, acknowledging that the single administration was studied for non-detection but the risk of recurrence from viable eggs was still monitored. Additionally, studies consistently explored limited non-detection against extitTrichuris trichiura (whipworm). Comparative evidence is lacking regarding its general non-detection against this specific parasite species.

Key Studies & References Pyrantel - Clinical and Research Information on Drug-Induced Liver Injury (NBK548238)

Frequently Asked Questions (FAQ)

Common questions about Anthel (FAQ)


Q: Is Anthel the same type of medicine as other similar-sounding drugs?

Anthel, which contains the active ingredient Pyrantel Pamoate, is formally classified as an anthelmintic agent. This classification refers to medicines used to treat parasitic worm infections. According to official product information, it belongs to the chemical class of tetrahydropyrimidine derivatives.


Q: Is Anthel known to interact with common pain relievers?

Official drug interaction information details specific known drug-to-drug interactions, such as the restriction on co-administration with Piperazine. Other common over-the-counter pain relievers are generally not listed in the main interaction warnings. Regulatory agencies emphasize the importance of informing healthcare providers about all medicines and supplements being used.


Q: Can Anthel be taken by older adults or seniors?

Official patient eligibility criteria state that the product is permitted for adults and children two years of age and older. The official labeling does not outline specific warnings or dosage adjustments for the general population of older adults.


Q: Does Anthel have a warning about driving or operating machinery?

Regulatory documents note that Anthel may cause side effects like dizziness or drowsiness. Official guidance notes that due to the potential for these effects, activities requiring full alertness, such as driving or operating machinery, may need to be approached with caution.


Q: Is it normal to feel tired after starting Anthel?

Official safety information lists drowsiness and fatigue as common, mild, and transient side effects of Anthel. The appearance of drowsiness is consistent with the side effects documented in the official safety profile for the medication.


Q: Is Anthel considered a narcotic or controlled substance?

No, Anthel (Pyrantel Pamoate) is not listed as a controlled substance or narcotic by major regulatory or drug-control agencies.


Q: Is Anthel available over the counter in any country?

Anthel (Pyrantel Pamoate) is classified as an Over-The-Counter (OTC) medication for specific indications in certain jurisdictions, including the United States. This means it can often be purchased without a prescription.


Q: Are there any known food restrictions while using Anthel?

Official documentation advises that grapefruit products should be avoided while taking this medicine due to the potential for increased drug levels. Official labels advise that the drug is often administered with a meal, particularly one containing fat, to enhance the absorption of the active metabolite.


Q: Does Anthel require a special type of prescription?

Anthel is widely available in the United States as an Over-The-Counter (OTC) Monograph Drug for specific indications. This classification means that a special or scheduled prescription is typically not required for its purchase in those instances.


Q: Can Anthel cause dizziness or lightheadedness?

Yes, regulatory documents list dizziness and headache among the common effects that sometimes occur. These nervous system effects are generally described as mild and transient in the official safety summaries.


Q: What is the typical time frame for the expected duration of Anthel’s effect?

The drug's therapeutic goal is achieved via the expulsion of parasites. Clinical trials monitoring effectiveness typically assessed outcomes related to the non-detection of the infection at a follow-up interval of two to four weeks post-administration.


Q: Is Anthel a common cause of drug interactions?

Official documentation identifies specific, known interactions that restrict its co-administration with other substances, such as Piperazine. While this indicates its potential to interact, regulatory documents do not broadly classify it as a 'common' or 'frequent' cause of interactions.


Q: Are there different strengths or formulations of Anthel?

Yes, Pyrantel Pamoate is documented to be available in multiple dosage forms for oral administration. These include both oral suspension and various tablets (e.g., chewable tablets), which are produced in different strengths.


Q: Does Anthel affect fertility or reproductive health?

Non-clinical studies, such as those conducted in animals, have examined reproductive effects. These studies have described no evidence of harm to fertility, reproduction, or lactation at the doses tested.


Q: Are there any reports about Anthel causing sleep disturbances?

The primary safety information lists drowsiness as a common side effect. While trouble sleeping or other sleep disturbances have appeared in post-marketing reports, they are not consistently listed as common effects in the primary regulatory warnings.


Q: What is the general success rate of Anthel in clinical trials?

Efficacy is measured using metrics like the Parasitological Cure Rate, which assesses the non-detection of the parasite after treatment. Systematic reviews have reported cure rates for pinworm infection in the range of 94% to 96%.


Q: Why is it important to follow the recommended schedule for Anthel?

Official warnings emphasize that the product's use structure, which often involves a single application, is intended to prevent excessive or unnecessary use. Following the prescribed guidance is therefore critical for its intended purpose.


Q: Are there any specific safety classifications for Anthel (like a Black Box Warning)?

Official regulatory labels outline specific contraindications (conditions where use is prohibited) and population-specific cautions (e.g., for liver disease). However, Anthel (Pyrantel Pamoate) does not have a Black Box Warning listed in the primary patient-facing safety summaries.

How should Anthel be stored and disposed of?

How to Store and Dispose of Anthel (Pyrantel Pamoate)

Official regulatory labeling dictates specific conditions for storing and disposing of Anthel to maintain its stability and safety.

Storage Requirements

Condition Regulatory Requirement
Temperature Store at controlled room temperature, typically 20 C to 25 C (68 F to 77 F).
Protection Keep from freezing and protect from light and excessive moisture.
Container Keep the container tightly closed and store the medicine in its original packaging.
Child Safety Keep out of the reach of children to prevent accidental ingestion.

Disposal Requirements

Disposal of unused or expired Anthel must be conducted in accordance with applicable local laws and regulations. Do not discharge the medicine into drains, sewer systems, or general wastewater. If a formal drug take-back program is unavailable, the product should be prepared for household trash according to established environmental guidelines.

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

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