pyrvinium

Action and Spectrum

Actions and spectrum: 

pyrvinium is an anthelmintic medication primarily used to treat pinworm infections. Its action involves paralyzing and killing parasites like pinworms, preventing them from attaching to the intestinal wall and allowing them to be eliminated from the body.

Its spectrum of activity is most effective against pinworms (Enterobius vermicularis) and some other intestinal parasites, and it may not be effective against a wide range of parasites. 

Drug Interaction

Adverse Reaction

Frequency not defined 

Nausea 

abdominal pain 

vomiting 

allergic reactions 

Headache 

Black Box Warning

Black Box Warning: 

There is no specific black box warning associated with pyrvinium. 

Contraindication / Caution

Contraindication/Caution: 

Contraindication: 

• Hypersensitivity: Individuals with a known hypersensitivity or allergy to pyrvinium or any of its components should avoid using this medication. 
• Severe Liver Disease: Individuals with severe liver disease or impaired liver function should use pyrvinium with caution, as it may be metabolized by the liver. 
• Renal Impairment: pyrvinium is primarily excreted through the kidneys. Individuals with significant renal impairment or kidney disease should use pyrvinium with caution, and dosage adjustments may be necessary. 
• Children: pyrvinium is considered safe for use in children for the treatment of pinworm infections, but dosages should be carefully adjusted based on the child’s age and weight.

Caution: 

• Allergic Reactions: Although rare, allergic reactions to pyrvinium may occur. If you experience symptoms of an allergic reaction, such as rash, itching, swelling, dizziness, or difficulty breathing, seek immediate medical attention. 
• Pregnancy and Lactation: The use of pyrvinium during pregnancy and lactation should be approached with caution. Consult with a healthcare provider before using pyrvinium if you are pregnant or breastfeeding to weigh the potential benefits against potential risks. 
• Pediatric Use: pyrvinium is often used in children for the treatment of pinworm infections. However, the dosage should be adjusted based on the child’s age and weight, and its use in infants requires special consideration.

Comorbidities: 

• Gastrointestinal Disorders: Patients with pre-existing gastrointestinal conditions, such as inflammatory bowel disease (IBD) or severe gastritis, may experience an exacerbation of their symptoms with pyrvinium use. Consultation with a healthcare provider is advised. 
• Liver Impairment: Individuals with liver disease or impaired liver function may need dosage adjustments or increased monitoring when using pyrvinium, as it is metabolized by the liver. 
• Allergies: Individuals with known allergies to pyrvinium or any of its components should avoid using the medication to prevent allergic reactions. 

Pregnancy / Lactation

Pregnancy consideration: pregnancy category: not assigned 

Lactation: excreted into human milk: unknown  

Pregnancy category: 

• Category A: well-controlled and Satisfactory studies show no risk to the fetus in the first or later trimester. 
• <b>Category B: there was no evidence of risk to the fetus in animal studies, and there were not enough studies on pregnant women. 
• Category C: there was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.   
• Category D: adequate data with sufficient evidence of human fetal risk from various platforms, but despite the potential risk, and used only in emergency cases for potential benefits. 
• Category X: Drugs listed in this category outweigh the risks over benefits. Hence these categories of drugs need to be avoided by pregnant women. 
• Category N: There is no data available for the drug under this category. 

Pharmacology

Pharmacology: 

pyrvinium is an antiparasitic medication primarily used to treat pinworm (Enterobius vermicularis) infections. Its pharmacology involves a unique mechanism of action. pyrvinium works by inhibiting the parasite’s cellular respiration, disrupting its energy production. It targets a crucial enzyme called mitochondrial ATPase, which is essential for the parasite’s survival.

By interfering with energy metabolism, pyrvinium effectively eliminates pinworms and helps relieve associated symptoms like itching and discomfort. pyrvinium is typically administered orally, and it is well-absorbed in the gastrointestinal tract.

After absorption, it is metabolized in the liver and excreted primarily in the feces. The medication is considered safe and effective for the treatment of pinworm infections, with a well-established record of use, especially in pediatric populations.  

Pharmacodynamics: 

• Inhibition of Mitochondrial ATPase: pyrvinium targets a crucial enzyme in the parasite’s mitochondria, known as mitochondrial ATPase. This enzyme is essential for the generation of adenosine triphosphate (ATP) for various cellular processes. By inhibiting mitochondrial ATPase, pyrvinium disrupts the parasite’s ability to produce ATP. 
• Disruption of Energy Metabolism: With mitochondrial ATPase inhibited, the parasite experiences a significant disruption in its energy metabolism. This impairs its ability to perform essential functions, including movement and reproduction. 
• Parasite Death: The interference with energy production leads to the death of the parasite. pyrvinium effectively starves the parasite of the energy it needs to survive, making it a potent anthelmintic agent. 
• Symptom Relief: By killing the parasites and reducing their numbers in the host’s body, pyrvinium provides relief from the symptoms associated with pinworm infections, such as itching and discomfort.

Pharmacokinetics: 

Absorption 

pyrvinium is usually administered orally in the form of tablets or suspension. It is absorbed in the gastrointestinal tract. 

Distribution 

pyrvinium is distributed throughout the body, and its concentration is highest in the gastrointestinal tissues. 

Metabolism 

pyrvinium metabolism in humans is not well-documented, but it may undergo hepatic (liver) metabolism. 

Elimination and excretion 

pyrvinium and its metabolites are primarily excreted through the feces, indicating that a significant portion is eliminated in the bile. 

Adminstartion

Administration: 

• Dosage: The dosage of pyrvinium can vary based on the individual patient and the condition being treated. pyrvinium is commonly available in tablet or suspension form.  
• Timing: It is essential to take pyrvinium exactly as prescribed. The timing of administration, such as whether it should be taken with or without food, will depend on your specific treatment plan.  
• Duration: The duration of pyrvinium treatment will also vary based on the condition being treated. Finish the course of treatment even if your symptoms improve before the medication is completed. This is important to ensure that the infection is completely eradicated. 
• Suspension: If you are using a pyrvinium suspension, carefully measure the prescribed dose using the provided measuring device (e.g., a dosing spoon or syringe). Shake the suspension well before use. 

Patient Information Leaflet

Patient information leaflet 

Generic Name: pyrvinium 

Pronounced: (pir-VIN-ee-um)  

Why do we use pyrvinium? 

pyrvinium is frequently used to treat pinworm infections, which are intestinal parasitic infections caused by Enterobius vermicularis. It helps eliminate the pinworms and relieve associated symptoms like itching around the anal area. pyrvinium may also be prescribed to treat other intestinal worm infections, such as hookworm, roundworm, or whipworm, although it is not the first-line treatment for these infections.