Skin Abscesses

Painted illustration of a skin abscess in a dog

What is it?

An abscess is a collection of pus caused by bacterial infection. Abscesses under the skin (subcutaneous abscesses) most often follow a bite from another animal, but sticks, grass seeds, or a previous infection at the same spot can also cause them. Abscesses can also form elsewhere, such as at a tooth root or in an anal sac.

What signs should I watch for?

A skin abscess usually appears suddenly as a painful swelling that may be firm or squishy like a water balloon, often with redness. It may burst and drain foul-smelling pus. Many dogs have a fever, even after the abscess has drained.

How is it diagnosed and treated?

Your veterinarian will examine the swelling and remove the pus, either by draining and flushing it or by surgery. Any foreign object must be removed, or the abscess will return. Antibiotics are a key part of treatment and should be given for the full course, along with pain medication. Rest and a quiet recovery help the tissue heal.

Can it be prevented, and what's the outlook?

For bite-wound abscesses, preventing fights is the best prevention.
Watch the site for increased draining while it heals.
Delayed or incomplete treatment can lead to chronic draining tracts, but with proper drainage, antibiotics, and follow-up, dogs usually recover completely.

Reviewed by the Adler Veterinary Hospital veterinary team, October 2026.

Dogs that fight or get sticks or grass seeds under the skin

Who's at risk:

Sudden painful swelling, redness, draining pus, fever

Main signs:

See a vet within a day or two

Urgency:

When to call a vet right away