Pyrantel
Pyrantel pamoate / Pyrantel embonate
Also known as: Drontal · Cazitel · Cestem · Dolpac · Endoguard · Prazitel · Veloxa · WORMclear · Pyrantel pamoate · Pyrantel embonate
Reviewed by the VetSheet Veterinary TeamUpdated Apr 5, 2026Evidence-based veterinary reference
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Dosing by species
🌎 NA — North America🌍 EU — Europe
Dogs
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Control of Toxocara canis, Toxascaris leonina, Trichuris vulpis, Uncinaria stenocephala, and Ancylostoma caninum | 5 mg/kg pyrantel + 15 mg/kg febantel or 20 mg/kg oxantel | PO | repeat as required | Single dose, repeat as required | 🌍 EU |
- Control of Toxocara canis, Toxascaris leonina, Trichuris vulpis, Uncinaria stenocephala, and Ancylostoma caninum: Often administered as a combination product.
Cats
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Control of susceptible gastrointestinal nematodes | 57.5 mg/kg pyrantel embonate | PO | repeat as required | Single dose, repeat as required | 🌍 EU |
- Control of susceptible gastrointestinal nematodes: Equivalent to approximately 20 mg/kg pyrantel base.
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Overview
Pyrantel is a broad-spectrum anthelmintic widely used in veterinary medicine for the control of gastrointestinal nematodes, specifically ascarids (roundworms) and hookworms (Toxocara canis, Toxascaris leonina, Uncinaria stenocephala, and Ancylostoma caninum). It is frequently formulated in combination with febantel or oxantel to expand its spectrum of activity to include whipworms (Trichuris vulpis), or with praziquantel to target tapeworms.
Clinical Pearl: Pyrantel is poorly absorbed from the gastrointestinal tract. This pharmacokinetic property is highly beneficial, as it allows the drug to reach high concentrations in the gut lumen where the target parasites reside, while minimizing systemic exposure and contributing to a wide margin of safety in the host.
Mechanism of action
Pyrantel acts as a depolarizing neuromuscular blocking agent in susceptible parasites. It functions as a cholinergic agonist at the nicotinic acetylcholine receptors of the nematode → causes continuous depolarization of the parasite's muscle cell membrane → results in spastic paralysis of the worm. The paralyzed parasites lose their attachment to the intestinal wall and are subsequently expelled from the host's gastrointestinal tract via normal peristalsis.
Safety & warnings
Contraindications
- Puppies < 2 months of age
- Puppies < 1 kg body weight
- Pregnant animals (safety not established)
- Lactating animals (safety not established)
Adverse effects
- Vomiting
- Diarrhoea
Precautions
Age and Weight Restrictions: Do not use in puppies under 2 months of age or weighing less than 1 kg. Reproductive Safety: Safety has not been established in pregnant or lactating animals; use is not recommended. Dosing Note: Pay close attention to the formulation. Some formulations express doses in terms of pyrantel base, while others use pyrantel embonate/pamonate (50 mg pyrantel base is equivalent to 144 mg pyrantel embonate/pamonate).
Drug interactions
Synergistic effect against whipworms
Synergistic effect against whipworms
Antagonistic mechanisms of action (piperazine causes flaccid paralysis, pyrantel causes spastic paralysis)
Similar mechanism of action; concurrent use increases the risk of cholinergic toxicity
Increased risk of cholinergic toxicity
Monitoring
- Resolution of clinical signs (e.g., diarrhea, poor weight gain)
- Fecal flotation/egg counts to confirm parasite clearance
Pharmacokinetics
Half-life
Absorption
Poorly absorbed from the gastrointestinal tract, allowing high concentrations to remain in the gut lumen to act on intestinal parasites.
Distribution
Minimal systemic distribution due to poor absorption.
Metabolism
The small fraction that is absorbed is rapidly metabolized in the liver.
Elimination
Primarily excreted unchanged in the feces. The small absorbed fraction is excreted in the urine as metabolites.
Overdose
Due to its poor gastrointestinal absorption, pyrantel has a wide margin of safety. Massive overdosage may result in systemic cholinergic signs, including salivation, vomiting, tremors, ataxia, and dyspnea. Treatment is supportive and symptomatic.
Available products
Formulations
- 10 mg tablet
- 50 mg tablet
- 80 mg tablet
- 87 mg tablet
- 120 mg tablet
- 125 mg tablet
- 175 mg tablet
- 5 mg/ml oral liquid
Veterinary
- Anthelmin
- Cazitel
- Cestem
- Dolpac
- Drontal
- Endoguard
- Prazitel
- Veloxa
- WORMclear
Human-labeled
- Combantrin
- Pin-X
Regulatory status
Available OTC in many formulations.
Classified as POM-V in the provided monograph, though some formulations may be available under different distribution categories depending on the member state.
Classified as POM-V (Prescription Only Medicine - Veterinarian) for specific proprietary products, though some anthelmintics are NFA-VPS.
No regulatory data for: 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Storage & stability
Store at room temperature in tightly closed containers, protected from light and moisture.
Client information
- Can be given with or without food.
- Mild side effects such as vomiting or diarrhea may occasionally occur after administration.
- Wash hands thoroughly after handling the medication.
- Ensure accurate dosing, especially in small puppies or kittens. Do not use in puppies under 2 months of age or weighing less than 1 kg.
- You may see dead worms in your pet's stool after treatment.
VetSheet drug reference is intended for licensed veterinary professionals as a clinical decision-support aid, not a substitute for professional judgement or the manufacturer’s current label.