What you see. The starting point for addressing any equine health related issue is your observation.


Purple, Red or Dark Spots on Gums or inside Nostril


There are a few areas on the body that provide important information regarding the state of a horse's circulatory health. These areas include the gums, the whites of the eyes, and the pink inner vulvar membranes of mares. Another window into the horse's health is the pink membrane visible inside the horse's nostril. The simple act of evaluating the color of this area is a very helpful skill.

Some diseases cause inflammation of the blood vessel wall, cause vessels to leak blood into the tissues (vasculitis). In horses with vasculitis, this area to appears purple, red, dark spotted or blotched. Examples are clotting disorders and disorders of the blood vessel walls themselves. This particular finding can be especially obvious in the glistening pink membrane inside the nostril. Keep in mind though that purplish discoloration of the gums can also be traumatic (bruising of the tissues).

  • Code Red

    Call Your Vet Immediately, Even Outside Business Hours
    • If the results of the Whole Horse Exam (WHE) in the resting horse indicate fever (Temp >101F/38.3C) or heart rate greater than 48 BPM.
  • Code Orange

    Call Your Vet at Their First Available Office Hours
    • If the problem is subtle or slowly changing.
    • If the results of the Whole Horse Exam (WHE) suggest the horse is otherwise normal.

your role


What To Do

Assess your horse's general health using the Whole Horse Exam (WHE) and reassess the color of their gums or nostrils after gently wiping the membranes off with a thumb or paper towel. Compare the appearance here to the gum color. Look for similar blotches there and on the whites of the eyes. Look for evidence of problems or abnormalities elsewhere. Especially look for swelling of the lower limbs, a finding that can be seen with blotching of the gums and can indicate leaky blood vessels (vasculitis).

Keep in mind that it takes some practice to recognize what may be abnormal. It is easy to confuse the normal, webbed appearance of the network of small vessels inside the nostril with an abnormality, especially in foals. Also, traumatic injury can occur here too, and can cause a similar appearance. Could the horse have suffered trauma to this area?

Share your findings and concerns with your vet.

your vet's role

In vet speak, red or purple spots on the mucous membranes are called petechia, and they are a sign of vasculitis (inflammation or damage to blood vessels). Your vet looks for other signs of vasculitis and performs tests that rule out the common causes. But petechia can also appear similar to bruising from trauma. The appearance of the condition and presence or absence of other signs helps differentiate between these.
Questions Your Vet Might Ask:
  • What is the horse's age, sex, breed and history?
  • Does the horse's appetite and attitude seem normal?
  • When did you first notice this?
  • Do the whites of the horse's eyes look normal?
  • What is the appearance of the horse's gums?
  • Do you notice swelling of the underbelly or groin?
  • Is there swelling of your horse's limbs or muzzle?
  • Is there swelling of the sheath?
  • Do you notice signs of any other problem?
  • Does the horse have a history of trauma to the area?
  • What are the results of the Whole Horse Exam (WHE)?
  • Do you notice any other signs of trauma?

Diagnoses Your Vet May Consider

The cause of the problem. These are conditions or ailments that are the cause of the observations you make.

Very Common
Less Common
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Treatments Your Vet May Recommend

A way to resolve the condition or diagnosis. Resolving the underlying cause or treating the signs of disease (symptomatic treatment)

Very Common
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Author: Doug Thal DVM Dipl. ABVP