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


Neck Swelling


When considering swelling of the neck, it helps to roughly divide the neck into thirds, and to know the very basic anatomy of the regions. The upper region, under the mane, is mostly composed of ligament tissue. The middle third is the flat, muscular region commonly used for intramuscular injection, and the lower region contains the spinal column and jugular groove. There are important structures that run through the lower region, including the jugular vein, carotid artery and major nerves. Injury to these structures can be serious and so swelling here must be taken seriously. See the Quick reference image of head and neck.

Swelling of the upper region is rare and is most common after a misplaced, high IM injection. The middle region swells most commonly as a result of injection reaction. The lower region swells with spinal column injury, and any misplaced IV injection. Damage to the jugular vein can result in swelling here as can heart failure with blood backup into the jugular vein. Fractures and injury of the spine can be associated with swelling here too. Damage to the trachea allows air to escape and become trapped under the skin. This causes a specific type of crackly, soft swelling. Traumatic injury is possible in any region.

  • Code Red

    Call Your Vet Immediately, Even Outside Business Hours
    • If this problem seems severe and has come on suddenly.
    • If you think your horse may have sustained a fracture or other severe injury.
    • If you notice apparent wobbliness or weakness, in addition to this sign.
    • 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 results of the Whole Horse Exam (WHE) suggest the horse is otherwise normal.
    • If the swelling is mild or moderate, and not increasing rapidly.
    • If the condition does not seem to be causing pain or other problem.
You also might be observing
Very Common
Less Common
more observations

your role


What To Do

Assess the horse's general health using the Whole Horse Exam WHE), paying particular attention to rectal temperature and heart rate. Gently examine and press on the area. Is it hard or soft, hot, or swollen? Does your horse exhibit a pain response when touched? Take a photo of the swelling. Share it, and your findings and concerns with your vet.

What Not To Do

NEVER purchase a horse with a swelling here without a veterinary pre-purchase exam!

your vet's role

Your vet assesses overall health, considers the horse's history and carefully assesses the area and the involved anatomy. Ultrasound and x-ray are commonly used diagnostics to help assess this area.
Questions Your Vet Might Ask:
  • How is the horse's attitude and appetite?
  • Does pressure on the area seem to cause the horse pain or discomfort?
  • Does the horse have a history of any illness or condition?
  • Has the horse recently received an intramuscular injection in the neck?
  • When was the horse injected?
  • Do you notice heat in the area?
  • Did you try to give the horse an intravenous injection?
  • Can you send a photo?
  • Has the horse recently been hospitalized?
  • What are the results of the Whole Horse Exam (WHE)?

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
more diagnoses

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
more treatments

Author: Doug Thal DVM Dipl. ABVP