Brand: STONGID-P ® ORAL PASTE 43.90% w/w

Company: ELANCO

FORMULATION: «oral paste» in pre-charged syringes

ACTIVE INGREDIENT(S)pyrantel embonate (=pamoate): 43.90% (= 430 g/kg)

CHEMICAL CLASS of the active ingredient(s): tetrahydropyrimidine



PARASITES CONTROLLED* (spectrum of activity)

* Country-specific differences may apply: read the product label.


*Can be slightly different in some countries: read the product label!


  • single oral dose of 19 mg pyrantel embonate per kg bodyweight (~6.6 mg/kg pyrantel base) for the control and treatment of strongyles (redworm), Oxyuris (seatworm/pinworm) and Parascaris (roundworm).
    • Up to 150 kg ¼ oral doser (marked 150 kg)
    • 51 kg to 300 kg ½ oral doser (marked 300 kg)
    • 301 kg to 450 kg ¾ oral doser (marked 450 kg)
    • 451 kg to 600 kg Full oral doser (marked 600 kg)
  • 38 mg pyrantel embonate per kg bodyweight (twice the dose rate for strongyles) for the control and treatment of Anoplocephala perfoliata (tapeworm).


LD50 (acute oral) in rats: >5000 mg/kg.

Estimated hazard class according to the WHO: not applicable for veterinary medicines

Suspected poisoning? Read the articles on pyrantel safety in this site.

Withholding periods (=withdrawal times) for meat (country-specific differences may apply: read the product label)

    • USA: Do not use in horses intended for human consumption.
    • UK Horse meat: zero days.

WARNING !!!: Never use on humans, dogs or cats


Risk of resistance? YES

This means that if this product does not achieve the expected efficacy against the mentioned parasites, it may be due to resistance and not to incorrect use, which is usually the most frequent cause of product failure.

Alternative chemical classes/active ingredients to prevent resistance of gastrointestinal roundworms through product rotation:

These alternative products may not be available in all countries, or may not be available as oral pastes or gels.

Learn more about resistance and how it develops.


Are the active ingredients of this product ORIGINAL* or GENERICS**?


*Meaning that they are still patent protected and generics are not yet available
**Meaning that they have lost patent protection and may be acquired from manufacturers of generic active ingredients other than the holder of the original patent.

COUNTRIES where this product is marketed: UK and other EU countries. In the USA marleted by ZOETIS under the trade name STRONGID PASTE HORSE WORMER.

Click here to learn more about GENERIC vs. ORIGINAL drugs.


This product is a classic oral paste dewormer for horses from ELANCO with pyrantel.

Pyrantel is a veteran tetrahydropyrimidine introduced in the 1960s (by PFIZER → ZOETIS) that is moderately used in horses, abundantly in pets, but rather scarcely in ruminants. It is a narrow-spectrum anthelmintic effective against roundworms and a few tapeworms in the gut, but not against those in other organs (e.g. the lungs, the skin, etc). It is also ineffective against gastric bots (Gasterophilus spp) or whatever external parasites. 

Pyrantel has no residual effect, i.e. it kills the parasites after administration but does not protect against reinfestations. In year-round control programs the recommended treatment interval is usually 4 to 6 weeks.

For an overview and a list of the most used oral paste & gel brands click here.


This article IS NOT A PRODUCT LABEL. It offers complementary information that may be useful to veterinary professionals and users that are not familiar with veterinary antiparasitics. 

Information offered in this article has been extracted from publications issued by manufacturers, government agencies (e.g. EMEA, FDA, USDA, etc.) or in the scientific literature. No guarantee is given on its accuracy, integrity, sufficiency, actuality and opportunity, and any liability is denied. Read the site's DISCLAIMER.

In case of doubt contact the manufacturer or a veterinary professional.