Dog Health Signs: What Your Dog’s Body Is Trying to Tell You

Dogs cannot say “my stomach hurts.” What they can do is eat grass, vomit yellow bile, start drinking twice as much water, develop a new limp, or stop wanting to come downstairs. These are health signals — and reading them correctly is one of the most important skills you can develop as a dog owner. This guide teaches you the system.

Why knowing your dog’s baseline changes everything

Every health assessment starts with one question: is this normal for this dog? You cannot detect deviation from baseline if you don’t know what baseline looks like. This is why experienced dog owners often catch illness earlier than new owners — they have an established sense of their specific dog’s normal.

What to know about your dog’s baseline

• Normal resting heart rate: 60–140 bpm depending on size (smaller dogs run faster). Learn it by counting beats for 15 seconds and multiplying by 4.
• Normal resting respiratory rate: 15–30 breaths per minute. Watch the chest rise and fall for 30 seconds.
• Normal temperature: 38.3–39.2°C (101–102.5°F). A rectal thermometer gives you this.
• Normal appetite: Does your dog finish meals reliably? How fast? Do they leave food occasionally?
• Normal water intake: Dogs typically drink 50–100ml per kg of body weight per day. Know roughly how much your dog drinks.
• Normal energy level and sleep pattern: How many hours does your dog typically sleep? How much activity do they seek?
• Normal elimination: How many times per day, what consistency, any straining?

A monthly 5-minute physical check — running your hands along the body, checking ears, teeth, eyes, and coat — means you notice lumps, skin changes, and weight shifts before they become significant. This is not paranoia; it is maintenance.

Symptoms that are always urgent — go now, don’t wait

Digestive health signals

Vomiting — reading the type and frequency

Not all vomiting is equal. The content, colour, frequency, and context tell very different stories:

For the most common specific presentation — why dogs vomit yellow bile in the morning — the full article covers causes, home management, and when yellow vomiting becomes a vet visit.

Changes in appetite

A dog who skips one meal and is otherwise normal is usually fine. A dog who refuses food but acts otherwise normal for more than 48 hours warrants a call to your vet. A dog who refuses food and is also lethargic, vomiting, or showing any other symptom warrants a same-day appointment.

Eating grass

Dogs eating grass is one of the most common behaviours that prompts owner concern — and one of the least consistently understood. Most grass eating is normal behaviour with no medical significance. The specific pattern that warrants attention is sudden, urgent, compulsive grass eating with subsequent vomiting, which can indicate GI discomfort.

Bad breath

Bad breath in dogs is almost always dental disease — the most common health problem in adult dogs, affecting over 80% by age 3. It can also indicate kidney disease, diabetes, or GI conditions. Don’t normalise a dog’s bad breath as “just how dogs smell” — it is almost always a treatable cause.

Movement and mobility signals

Changes in how a dog moves are among the most consistently underreported health signals. Dogs are instinctively reluctant to show pain — vulnerability in a pack animal is a survival disadvantage — which means physical discomfort often expresses as movement changes rather than obvious pain behaviours.

What to watch for

• Limping after sleeping — stiffness that resolves once moving is a classic sign of arthritis or joint disease, not just “getting old”
• Reluctance to jump, climb stairs, or get on furniture they previously used — this is joint pain until proven otherwise
• Sitting differently — a dog who suddenly begins sitting with one leg out to the side, or who struggles to sit squarely, may be compensating for hip or lower back pain
• New gait changes — head bobbing, shortened stride, asymmetrical movement
• Difficulty lying down — circling repeatedly before lying, or lying down very slowly and carefully

Pain management in dogs has advanced considerably in recent years. A dog diagnosed with arthritis today has access to NSAIDs, newer drugs like Librela (monoclonal antibody therapy), joint supplements, hydrotherapy, and physiotherapy. There is no good reason for a dog to manage ongoing pain when so many effective options exist.

Energy and sleep signals

Lethargy — being unusually quiet, sleeping more than normal, reluctant to engage in activities they normally enjoy — is one of the most non-specific signs in veterinary medicine. It accompanies dozens of conditions. But it is always significant when it represents a real departure from that dog’s normal.

Dogs sleeping more than usual explores this in full: the benign causes (hot weather, post-exercise recovery, age), the moderate-concern causes (subclinical illness, anaemia), and the urgent causes (organ disease, toxin exposure, severe infection).

The 48-hour lethargy rule

Lethargy that persists for more than 48 hours without a clear benign explanation (very hot weather, a long and unusual amount of exercise the day before) warrants a vet call. If it’s accompanied by any other symptom — appetite changes, vomiting, increased water intake — the threshold is lower.

Skin, coat, and itch signals

The skin is the largest organ and one of the most expressive. Changes in coat quality, scratching patterns, and skin appearance often reflect systemic health issues, not just local skin problems.

Scratching and itching

Excessive scratching is almost always one of three things: environmental allergies (atopy), food allergies, or ectoparasites (fleas, mites). All three are treatable, but the treatment differs significantly. The distribution of the scratching is a useful diagnostic clue:

• Ears, face, belly, and feet — classic atopy/environmental allergy distribution
• Base of tail and hindquarters — flea allergy dermatitis; even if you don’t see fleas, they may be present
• Diffuse, whole-body scratching — food allergy or sarcoptic mange (a mite that is intensely itchy and highly contagious)

Coat quality changes

A dull, dry, or sparse coat can indicate nutritional deficiency, thyroid disease, Cushing’s disease, or parasites. A dog whose coat was previously healthy and has deteriorated deserves investigation beyond switching to a more expensive food.

Lumps and bumps

Any new lump discovered during your monthly physical check should be noted — its location, approximate size, whether it’s moveable or fixed, and whether it seems to be growing. Most lumps in dogs are benign (lipomas are extremely common in middle-aged dogs) but some are not, and early investigation changes outcomes for the ones that aren’t. Do not wait and watch a new lump indefinitely.

Thirst and urination signals

Excessive drinking in dogs — technically called polydipsia — is one of the most diagnostically significant signs a dog can show. It nearly always has a medical cause, and most of those causes are identifiable and treatable with a blood and urine panel.

Conditions commonly presenting with increased thirst

Increased thirst is also one of the conditions most commonly dismissed by owners as “they’re just thirsty” — particularly in warm weather. If your dog’s water consumption has meaningfully increased and stayed increased across different weather conditions, a vet visit is warranted. A urinalysis and basic blood panel provide enormous diagnostic information for a modest cost.

Neurological signals

Neurological signs in dogs range from subtle to unmissable. Some indicate true emergencies; others can be monitored over days. The key is recognising the difference.

Sudden shaking and trembling

This is one of the most anxiety-provoking things to witness in a dog because shaking can mean so many different things: being cold, being frightened, being in pain, nausea, low blood sugar, neurological events, toxin exposure, or an Addisonian crisis. The full guide to sudden shaking covers the diagnostic approach in detail. Urgent red flags alongside shaking: collapse, vomiting, diarrhoea, pale gums, loss of consciousness.

Sneezing

Why dogs sneeze repeatedly — occasional sneezing is normal (dogs sneeze to clear the nasal passages and as a calming signal). Persistent, repetitive sneezing, particularly if accompanied by discharge, blood, or favoring one nostril, warrants investigation. Foreign bodies in the nose, nasal tumors, and dental root abscesses that extend into the nasal cavity are all causes of chronic sneezing in dogs.

Pacing and disorientation

Unexplained pacing, particularly at night, combined with disorientation, failure to recognise familiar environments, or apparent confusion is the presentation of canine cognitive dysfunction in older dogs — or of vestibular disease (an inner ear problem that causes sudden, often dramatic balance loss and disorientation but resolves over days to weeks in most cases).

Senior dog health monitoring

Dogs are considered senior at approximately 7 years — earlier for giant breeds, later for small breeds. The monitoring approach for senior dogs is more intensive because more can go wrong, it can go wrong more quickly, and early intervention has a much larger impact on outcome.

Senior dog health red flags

• New or increasing stiffness — treatable arthritis vs other joint disease
• Sleeping significantly more than their previous normal — particularly important in seniors
• Night-time vocalisation or pacing — canine cognitive dysfunction
• Loss of previously reliable house training — multiple possible causes, all worth investigating
• Weight change in either direction — unexplained weight loss or gain in a senior dog requires blood work
• Lumps appearing or growing — more common in seniors; should not be assumed benign

Biannual vet visits

Dogs over 7 benefit from twice-yearly veterinary check-ups rather than the annual visits appropriate for younger adults. The reasoning is simple: dogs age faster than humans, and six months represents a proportionally longer period in a dog’s life. Many conditions are caught and managed far more effectively when they’re found at a biannual check-up rather than when the owner notices the symptoms.

The vet-or-wait decision framework

The decision of whether to go to the vet today, call tomorrow, or monitor for now is one of the most practically difficult aspects of dog ownership. Here is a framework that has proven consistently useful:

Go to emergency vet now

• Any of the emergency symptoms listed above
• Suspected toxin ingestion
• Trauma
• Dog cannot stand or is extremely distressed

Call your vet today (or go today if available)

• Multiple vomiting episodes in one day, or vomiting with any other symptom
• Blood in vomit, stool, or urine
• Lethargy lasting more than 24 hours
• Complete refusal of food for more than 24 hours
• Sudden limping that is not improving
• Dramatic increase in water consumption
• Any sudden neurological sign (shaking, disorientation, weakness)

Book a non-urgent appointment (within a week)

• Gradual changes in appetite, energy, or thirst over several weeks
• New lump discovered
• Persistent low-level scratching not responding to home management
• Bad breath that has been present for some time
• Gradual gait changes or mild new stiffness

Monitor at home (but document and reassess at 48 hours)

• One vomiting episode with no other symptoms in a dog who is otherwise normal
• One missed meal in a dog who is otherwise eating normally
• Mild, brief sneezing episode
• Temporary lethargy after unusual exercise in hot weather