Symptoms in dogs and cats
Symptoms are how the body tells you something is wrong. Some — like a single soft stool in a bright dog — settle quickly. Others — like open-mouth breathing in a cat or repeated unproductive retching in a deep-chested dog — are emergencies.
Every page in this section leads with the most useful first action, then explains how to recognise the symptom, what to do, what NOT to do, and when to phone the vet immediately. Pages are colour-coded by urgency.
Emergency — phone the vet now
- Cat
Blood in a cat's urine
Blood in cat urine, especially with straining, is an emergency in male cats — phone the vet now to rule out blocked bladder.
- Dog
Blood in a dog's vomit
Fresh red flecks or coffee-ground (digested) blood in vomit needs same-day vet contact; large amounts, repeated vomiting, or pale gums are emergencies.
- Cat
Cat breathing through an open mouth
Open-mouth breathing in a cat is always an emergency — phone the vet now; cats hide breathing problems until decompensation, and panic worsens it further.
- Cat
Cat having difficulty breathing
Phone your vet or emergency animal hospital IMMEDIATELY.
- DogCat
Dog or cat having a seizure (fitting)
Stay calm, do not touch the mouth, time the seizure, and clear furniture from around the pet.
- DogCat
Dog or cat that has collapsed
Check breathing and heartbeat, keep the pet flat on its side with airway clear, and drive to the emergency vet now.
- Dog
Dog struggling to breathe
Difficulty breathing in a dog is always an emergency — phone the vet now and head straight to the practice; do not delay for showers, food, or other tasks.
- Dog
Dog with blue or grey gums
Call your emergency vet NOW and start driving — blue or grey gums mean your dog's body is not getting enough oxygen.
- Dog
Dog with bright red gums
Bright red gums with panting, vomiting, or collapse could be heat stroke or sepsis — call your vet or emergency vet immediately and begin cooling if heat stroke is suspected.
- DogCat
Pale or white gums in dogs and cats
Pale, white, blue, yellow or muddy gums always need an emergency vet — they are a sign of poor oxygen, blood loss, shock, or poisoning.
- Cat
Yellow gums or eyes in a cat (jaundice)
Yellow gums, eyes, or inner ears in a cat indicate liver problems and are always an emergency — phone the vet now.
Urgent — same day vet contact
- Dog
Blood in a dog's stool
A small streak of fresh blood with otherwise normal stools and a bright dog can be monitored briefly; black tarry stool, large blood volumes, or any unwell dog needs same-day vet contact.
- Dog
Blood in a dog's urine (haematuria)
Visible blood in urine needs vet review the same day — UTIs, bladder stones, prostate disease, and tumours all present this way.
- Cat
Cat coughing — when to worry
Cats cough far less than dogs — any persistent cough warrants a vet visit, and any breathing difficulty alongside is an emergency.
- Cat
Cat hiding or acting differently
Cats hide pain and illness — sudden hiding, withdrawal, or behavioural change usually signals a medical problem; book a vet check.
- Cat
Cat limping or holding up a leg
Cats hide pain well — any limp lasting more than 24 hours, any non-weight-bearing leg, or any cat with visible swelling or wound needs a same-day vet visit.
- Cat
Cat refusing to eat (anorexia)
A cat that has not eaten for 24 hours needs vet contact today — feline hepatic lipidosis (fatty liver) can develop within 2–3 days of fasting and is life-threatening.
- Cat
Cat scratching ears, head shaking, or ear discharge
Black coffee-ground discharge in a kitten or young cat is typically ear mites; persistent scratching, head shaking, or pain in any cat needs vet review within a few days.
- Cat
Cat straining in the litter tray
Contact your vet today.
- Cat
Cat that has stopped grooming
Reduced grooming or matted coat in a cat is rarely behavioural — it usually signals pain, illness, or arthritis; book a vet appointment.
- Cat
Cat vomiting — when to worry
A cat vomiting more than once or twice in 24 hours, going off food, or hiding needs same-day vet contact — cats decompensate fast.
- Cat
Cat with diarrhoea — when to worry
Mild loose stool in a bright, eating cat can be monitored briefly; any blood, lethargy, refusal to eat for over 24 hours, or kitten with diarrhoea needs vet contact today.
- Dog
Dog coughing — when to worry
An occasional cough in a bright dog is rarely urgent; persistent coughing, soft moist cough with froth, breathing changes, or any blue-tinged gums needs the vet now.
- Dog
Dog drinking more water than usual (polydipsia)
A persistent increase in thirst is rarely benign in dogs — book a vet appointment within a few days; sooner if accompanied by vomiting, weight loss, or unspayed female dogs after a season.
- Dog
Dog limping or holding up a leg
Check the paw for cuts, splinters, or broken nails first; rest and monitor mild limping for 24 hours, but any non-weight-bearing leg, severe pain, or visible deformity needs the vet today.
- Dog
Dog scooting, licking back end, or smelly back end (anal glands)
Scooting, excessive licking, or a fishy smell often points to anal gland issues — a vet or trained nurse can express the glands; never try at home without training.
- Dog
Dog scratching ears, head shaking, or ear discharge
Persistent scratching, head shaking, or smelly ear discharge points to ear infection or foreign body — book a vet appointment promptly to prevent ear-drum damage and chronic disease.
- Dog
Dog shaking head persistently
Persistent head shaking points to ear problem, foreign body, or in rare cases neurological disease — book a vet visit promptly to prevent ear haematoma and middle-ear damage.
- Dog
Dog straining to defecate (constipation or obstruction)
Mild straining with eventual production of stool is usually constipation; persistent straining producing nothing, with vomiting or distress, can mean obstruction and needs the vet today.
- Dog
Dog vomiting — when to worry
Withhold food for 4–6 hours, offer small sips of water, and phone the vet if vomiting repeats, contains blood, or the dog seems unwell.
- Dog
Dog with a swollen muzzle or face
A suddenly swollen face needs veterinary assessment today — if your dog also has pale gums, breathing difficulty, or collapses, treat as an emergency and call the vet now.
- Dog
Dog with diarrhoea — when to worry
A bright dog with mild loose stool can be managed at home for 24 hours with bland food; blood, repeated episodes, lethargy, or any puppy/senior needs a same-day vet call.
- Dog
Persistent sneezing in dogs
Sudden violent sneezing, especially after sniffing in grass, can be a foreign body; persistent sneezing or bloody nasal discharge needs vet review.
- Dog
Skin mass that's growing or changing on a dog
Any rapidly growing, ulcerating, or changing skin lump needs prompt vet review with fine-needle aspirate or biopsy — early diagnosis matters.
- Dog
Sudden aggression or growling in a usually friendly dog
A sudden change to growling or snapping in a previously friendly dog often signals pain — book a vet visit; do not punish or correct, this can mask important warning signs.
Monitor — routine vet appointment
- Dog
Dog not eating (loss of appetite)
One missed meal is rarely serious — monitor closely.
- Dog
Dog with bad breath (halitosis)
Bad breath is rarely 'just dog breath' — book a dental check; persistent halitosis usually means dental disease and sometimes points to systemic illness.
- Dog
Dog with itchy skin (chewing, licking, scratching)
Persistent itching deserves a vet appointment — fleas, allergies, and mites all need different treatments, and self-trauma escalates quickly into hot spots and infection.
- Cat
Lump on a cat's skin
Check the lump's size, location, and texture, then book a vet appointment — any lump at a vaccination site that persists beyond 4 weeks or grows must be seen urgently.
- Dog
Lump on a dog's skin
All new lumps should be examined by a vet — most are benign, but mast cell tumours can look like anything and must be tested with a fine needle aspirate.
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