Grass Awns

A stroll around the region will show many of our grasses seeding. This means the start of the season where we see foreign body reactions due to migrating grass awns. The difficulty with the migrating grass awn is that they often cause pain and illness which is difficult to diagnose.

The grass awn is covered in “hairs” that are shaped like barbs, which promote forward migration. Once the awn has penetrated the skin it makes short work of the subcutaneous tissue. It is in this tissue, just under the skin, that the pet experiences an inflammatory response and if ignored, will cause a secondary bacterial infection. We often see an initial improvement in symptoms when the pet is placed on antibiotics at this stage. Once the antibiotic therapy is complete however, the symptoms resume.

Grass awns can migrate into the abdominal or thoracic cavity, often causing organ abscesses but these awns can migrate as far as to the prostate or the intervertebral discs.

Where the grass awns access the body and what symptoms to expect:





Awns visibly attached to coat

Inside the Ear


Shaking the head

Tilting head

In the Eye

Inflammed eye





Nasal discharge




Between the Toes



Small draining tract

Sore on the paw

Inhalation into Lungs/Migration to other Organs


Depressed/Weight loss


Shortness of breath

Diagnosis and Treatment:
Identifying the grass awn can be challenging. Although ultrasound can sometimes be useful to identify a subcutaneous mass where there is a small cavity surrounded by fluid, they are often not visible, making diagnosis difficult.
The treatment goal is to remove the grass awn and then support the surrounding tissue to heal. This can require surgery and antibiotic therapy as well as the use of anti inflammatories and pain medication.


  • Check your dog’s coat and especially the hair between the toes regularly and remove any grass seeds
  • Longer coated or fluffy dogs should have their hair trimmed between their toes
  • Brush your dog after a walk
  • Keep your dog on lead, on the pathways at the time of year the grass awns are most active
  • Consider some protective gear ie cooling vets for your dog to wear on walks, reduces the risk of picking up grass awns
  • Be aware of changes ie sudden ear discomfort or small wounds that have a discharge


Taking your dog into the vet promptly is a good idea to prevent serious health issues. Once the awn has punctured the skin it’s best not to remove them yourself. The grass awn have barbs and they can snap or break during the removal process leaving a tiny piece behind, leading to inflammation and infection.