Conditions or ailments that are the cause of a problem that you see - your observation.

Your vet may diagnose

Insect Stings, Centipede, or Spider Bites


Bites and stings are difficult to diagnosis. Often vets "back into" these diagnoses for lack of another explanation and by ruling out other potential diagnoses.

Insect stings and spider bites usually cause local swelling and an allergic response. In most cases, allergy is shown by local swelling and swelling around the eyes and face. In some cases, stings and spider bites can cause anaphylaxis, a life-threatening body-wide allergic response.

There are only two venomous spiders in the United States that are truly poisonous to horses. The Brown Recluse or Fiddleback causes tissue inflammation and sloughing at the bite site, eventually creating an open wound over several weeks. A bite from a Black Widow causes muscle rigidity at the bite site, and generalized muscle spasms. A horse bitten by a black widow may appear wobbly or walk stiffly, or show signs of colic.

DIAGNOSIS usually requires capture of the offending animal and evidence that it bit or stung the horse.

TREATMENT is usually symptomatic and aimed at minimizing inflammation and pain until signs subside.

my vet's role



Other conditions or ailments that might also need to be ruled out by a vet.

Very Common
Less Common
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Generally good, provided that there is no systemic allergic response. However, Black Widow envenomation can occasional be fatal in horses.

Author: Doug Thal DVM Dipl. ABVP