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Tailwise

Symptom · Dogs and cats

Lumps and bumps: what it means and when to call the vet

See a vet within 24 hours

Most lumps are harmless, but you can’t tell by feel. Any new lump, or one that is growing or changing, should be checked by a vet with a simple needle sample.

Common causes

  • Fatty lumps (lipomas) in older dogs
  • Cysts and warts
  • Abscesses after fights, especially in cats
  • Skin tumours such as mast cell tumours
  • Injection-site reactions

What you can do at home

  • Measure the lump and take a photo with a coin for scale
  • Note where it is on a body map

What the vet may do

  1. A fine-needle aspirate — a quick needle sample
  2. A biopsy if needed
  3. Surgery to remove lumps that need it

Prevention

  • Run your hands over your pet each month
  • Keep a record of every lump
Not sure how urgent it is?Answer a few questions about what you are seeing and the checker tells you whether to go now, call today or watch at home.Open the symptom checker

The details

Veterinary cancer specialists promote a simple rule of thumb — “see something, do something”: if a lump is the size of a pea or larger and has been there for a month, have it sampled. A needle sample is quick, usually needs no sedation, and often gives an answer the same day.

Questions owners ask

Is lumps and bumps an emergency?

Usually it is not an emergency, but your pet should see a vet within 24 hours. Go now if you see: a lump that is bleeding heavily; a hot, painful swelling with fever (possible abscess); a lump with weakness or pale gums.

What causes lumps and bumps?

Fatty lumps (lipomas) in older dogs; Cysts and warts; Abscesses after fights, especially in cats; Skin tumours such as mast cell tumours; Injection-site reactions.

What can I do at home?

Measure the lump and take a photo with a coin for scale. Note where it is on a body map.

Sources

  1. VCA Animal Hospitals: pet health library

Tailwise is for general information and is reviewed by veterinary professionals, but it is not a substitute for advice from your own vet, who knows your pet. How we check facts

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