Strongid T Side Effects

Strongid T is a popular brand of dewormer for horses, ponies, donkeys and mules made by Pfizer. Its active ingredient is pyrantel pamoate. It comes in a liquid and paste formulations. Some horses prefer the taste of the paste to the liquid. Pfizer recommends that Strongid T liquid be given a good shake before use. Strongid T is also used for roundworms and hookworms in dogs and cats.

  1. Side Effects in Horses

    • In horses, there are no known negative side effects of Strongid T. However, the horse will pass worms in its stool, which may be alarming. The stool may become loose.

    Long-Term Use

    • Worms in horses have been known to build a tolerance to dewormers, including Strongid T. Strongid T needs to be rotated with another brand of dewormer so the parasites do not become immune.

    Cats and Dogs

    • Side effects in cats and dogs include vomiting, straining to excrete, diarrhea, and passing dead and dying worms in stool.

    Rare Side Effects

    • According to Wendy C. Brooks, D.V.M., there is a small chance of a lethal side effect in dogs and cats. Too many dead worms may pass at once and cause an impaction that will need to be cleared.

    Warning

    • Brooks also mentions that Strongid T should not be given simultaneously with other dewormers such as levamisole, morantel or piperazine. This could increase the chance of a worm impaction, which could lead to a perforated bowel.