Combifrinil is commonly used to address specific parasitic infections of the gastrointestinal tract. The medication (Pyrantel) is used as an antiworm agent to treat infections caused by pinworms, roundworms, and hookworms.

Targeting Parasitic Conditions and Easing Discomfort

This medication is applied in conditions characterized by the presence of specific parasitic worms, particularly pinworm infection (Enterobiasis) and roundworm infection (Ascariasis). Combifrinil is commonly used when clinical presentation confirms these specific intestinal nematodes, and may assist with easing the parasite burden. It supports functional stability by addressing the source of the discomfort. It is relevant for easing symptoms related to nocturnal anal itching (pruritus), which can cause sleep disturbance, and abdominal discomfort. This helps address symptom clusters that may become intense or disruptive.

Support for Household Infection Management

Given the ease with which certain parasitic infections spread, Combifrinil is applied in scenarios where additional management of discomfort is required for all immediate cohabitants. It may be part of symptomatic management for close contacts, as this strategy is considered relevant for easing the transmission risk and supporting functional stability across the household.

The therapeutic role is to help patients cope more steadily with difficult episodes of discomfort and support general well-being during symptomatic phases.

Quick Fact: Addresses symptoms of Nocturnal Itching

Regulatory References

1. MedlinePlus Drug Information overview

Eligibility Profile: Official Regulatory Restrictions

Official regulatory documentation establishes clear criteria for who can and cannot use this medicine, primarily based on age, existing medical conditions, and physiological status.

Contraindicated and Restricted Populations

Age-Related Eligibility

The medicine is generally considered eligible for use in individuals 2 years of age and older, provided they meet all other criteria. For all restricted populations, physician consultation is required to assess individual risk before use.

Interactions with other medicines and products

The official regulatory profile for Combifrinil (Pyrantel) documents specific interaction patterns concerning co-administered medicinal products and certain ingestible substances. The interactions primarily relate to pharmacodynamic effects and the potential for altered systemic exposure to other drugs.

Official interaction statements:

• Co-administration with the anthelmintic agent Piperazine results in pharmacodynamic antagonism, which regulatory summaries advise should be avoided.
• The plasma concentration of Theophylline is officially documented to increase when co-administered with Pyrantel, an interaction classified as minor in some regulatory references.
• There is no clinically significant interaction with food, and the medication can be administered independently of meals.
• Co-ingestion of alcohol may exacerbate certain CNS effects, such as dizziness, which is a general substance-related risk.
• The profile includes a mandatory constraint: use is listed as a caution or contraindication in patients with impaired hepatic function.

Connection to the overall interaction profile (2–4 sentences): The regulatory documents define the product’s interaction structure through mandated restrictions on co-administration with Piperazine and noted systemic exposure modification of Theophylline. This profile is complemented by specific cautions regarding use in the context of co-occurring impaired hepatic function, due to the partial hepatic metabolism of the systemically absorbed amount of the drug.

The mechanism of Pyrantel involves the parasite's motor function by acting as an agonist at the nicotinic acetylcholine receptors ( nAChRs) found on the nerve-muscle connection of susceptible intestinal nematodes. This interaction initiates sustained stimulation of the parasite's neuromuscular pathway. The continuous activation of the nAChRs triggers a specific depolarizing neuromuscular blockade. This action forces the parasite's muscle cells into a state of sustained, uncontrollable contraction, resulting in spastic (tetanic) paralysis. This physiological change prevents the worms from maintaining attachment to the host's intestinal wall, which aligns with their passive removal via normal digestive motility. The mechanism of action is constrained by its target specificity. It is ineffective against certain species, such as Trichuris trichiura, and does not affect migrating or encysted parasitic forms located outside the intestinal tract.

Combifrinil (Pyrantel base) is administered exclusively via the oral route, typically as a liquid oral suspension or a chewable tablet. The administration is governed by a weight-based dosing principle, where the standard dose is calculated as 11 mg of Pyrantel base per kilogram of body weight. Regardless of body weight, the total dose administered must not exceed 1 gram (1000 mg) in a single administration.

The official use pattern for Pinworm infection involves a single administration course. To account for the full parasitic life cycle, instructions for use stipulate that this initial dose may be repeated two to three weeks later (14 to 21 days). For other infections, such as Hookworm, the approved pattern requires the dose to be given once daily for three consecutive days.

The medicine can be taken at any time of day and with or without food; fasting is not required. When using the oral suspension, the product must be shaken well before measurement, and an accurate measuring device must be employed to administer the precise, weight-based amount. The weight-based formula applies to both adults and children; however, the medicine is generally not recommended for children under 2 years of age or those weighing less than 25 pounds.

Research Evidence Overview for Combifrinil

Evidence for Use in Pinworm Infection (Enterobiasis)

The research on Combifrinil (Pyrantel Pamoate) for pinworm infection was studied through regulatory dossiers, systematic reviews, and randomized controlled trials (RCTs). These studies focused on measuring short-term outcomes related to physical discomfort and rates of parasite clearance. Researchers primarily examined whether the administration was associated with the rates of parasite clearance, which they measured through the rate of egg negativity (Cure Rate) in the immediate weeks following administration.

The research describes that data show patterns related to high measurements of egg negativity in the observed populations when evaluated shortly after administration. Because pinworm is a condition characterized by high re-infection risk, the studies monitored household contacts as well and explored the necessity of repeat administration protocols in that setting.

Evidence for Use in Roundworm Infection (Ascariasis)

Research has also explored Pyrantel Pamoate for its use in roundworm infection. The studies explored this through large-scale RCTs and systematic reviews. The main outcomes measured reflected changes in the number of parasites, specifically the rate of egg elimination (Egg Reduction Rate) and the overall Cure Rate in the weeks after administration.

The findings describe patterns observed in these studies, indicating patterns related to high measurements of egg negativity when assessed within one month. Studies exploring short-term symptom changes reported consistent results, contributing to the broader evidence landscape for this indication.

The Evidence Base for Hookworm Infection

Pyrantel Pamoate was also evaluated in research for hookworm infection. Research examined this through comparative trials against other treatments. When used as a single agent, evidence quality is observed to be heterogeneous across studies, and research describes that the rates of egg reduction were described as being dissimilar to the patterns observed for pinworm and roundworm. Certainty remains low regarding the research outcomes for its use as a monotherapy for hookworm in all settings.

What is Still Uncertain About Combifrinil’s Research Record

A key limitation is that follow-up durations were restricted, meaning long-term effects are not fully established. While short-term outcomes for pinworm and roundworm are generally described, data for certain groups, such as very young children, remain insufficient. Comparative evidence against alternative treatments is lacking in some areas, particularly for hookworm. Further research is ongoing to explore long-term outcomes and recurrence patterns.

Key Studies & References Pyrantel Pamoate Drug Information

Common questions about Combifrinil (FAQ)

Q: Is Pyrantel Pamoate a brand or generic drug?

Pyrantel Pamoate is the generic name for the active drug component found in Combifrinil. It is commonly sold under various brand names, including Combifrinil, and is classified as an over-the-counter medicine for pinworm treatment. Official documents define the substance by its generic name for regulatory purposes.

Q: Is Pyrantel Pamoate OTC or Prescription?

According to official regulatory bodies, Pyrantel Pamoate for treating pinworm infection is classified as an Over-the-Counter (OTC) drug under a regulatory monograph. This classification indicates that the medicine is generally available without a prescription for this specific approved use.

Q: What is the pill marking/imprint code for Pyrantel Pamoate?

The specific imprint code (letters or numbers) stamped on a tablet can vary based on the manufacturer and the specific product formulation. Official labeling may document different imprint codes, or sometimes no code, across various product entries. The code functions as a way to identify the particular product from the manufacturer.

Q: Does Pyrantel Pamoate cause weight gain or weight loss?

Official regulatory documents do not explicitly list weight gain or weight loss as documented adverse reactions. However, the lists of frequently reported side effects do include symptoms that can potentially affect food intake, such as a loss of appetite (anorexia) and various gastrointestinal effects like nausea and diarrhea.

Q: Can I take Pyrantel Pamoate with caffeine or other supplements?

Official drug interaction lists focus on specific prescription drugs and do not explicitly list caffeine or general dietary supplements as having documented interactions with this medicine. While regulatory documents may not state a specific restriction, regulatory guidance suggests providing healthcare providers with a list of all current medicines, supplements, or herbal products.

Q: Can I crush or split Pyrantel Pamoate tablets?

Official regulatory labeling for the tablet form of this medicine does not contain specific instructions or warnings regarding crushing or splitting the pill. In contrast, the official directions for the liquid oral suspension emphasize the need to shake well and use an accurate measuring device. Official use documentation supports administering the tablet as directed by the instructions on the package.

Q: Does Pyrantel Pamoate have a Black Box Warning?

Official regulatory labeling for Pyrantel Pamoate does not include a Black Box Warning (a boxed warning). This type of safety caution is typically applied to specific risks documented in clinical use. The product labeling does include specific cautions, such as warnings against exceeding the recommended dosage and the need for consultation if a patient has liver disease or is pregnant.

Q: Are there safety studies for Pyrantel Pamoate in older adults?

Clinical information, based on the studies supporting the product, indicates that there is no specific data available that compares the use of this medicine in older people with its use in other age groups. This suggests that the safety and efficacy information available is generally derived from the broader populations studied in clinical trials.

The storage and disposal instructions for Combifrinil (Pyrantel Pamoate) are strictly defined by regulatory labeling to ensure product integrity and household safety.

Storage Requirements

The medication must be stored in its original, tightly closed container at controlled room temperature, typically ranging from 15 C to 30 C (59 F to 86 F). Official labeling prohibits storing the product in areas of excess heat or moisture and explicitly states: Do not freeze. The product must be protected from direct light.

Safety and Disposal

It is mandatory to keep Combifrinil out of the sight and reach of children and pets to prevent accidental ingestion. For disposal, unused or expired medicine must not be flushed down a toilet or poured into a drain. The official method is to use a community drug take-back program or, if unavailable, mix the medicine with an undesirable substance (such as dirt or cat litter) before sealing it in a container for household trash disposal. Environmental guidelines advise avoiding release of the product into the environment.