Your dog cannot tell you when something is wrong. They cannot describe a headache, point to a sore joint or explain that their stomach has been troubling them for three days. As a dog owner, recognising the early signs of illness is one of the most important skills you can develop — because catching health problems early almost always leads to better outcomes, simpler treatment and significantly lower vet bills.
This comprehensive guide covers the 12 most common health problems in dogs: what causes them, what symptoms to watch for, when to see a vet urgently and what you can do at home. Whether you are a new dog owner or an experienced one, there is something here that could one day make a critical difference for your dog.
1. Ear Infections (Otitis Externa)
What it is
Ear infections are one of the most frequently diagnosed conditions in dogs. They occur when the ear canal becomes inflamed and infected — usually by bacteria, yeast or a combination of both. Some dogs suffer occasional ear infections; others struggle with chronic recurrent infections throughout their lives.
Symptoms to watch for
- Frequent head shaking or tilting the head to one side
- Scratching at one or both ears
- Dark, brown or black discharge from the ear canal
- Unpleasant odour coming from the ear
- Redness, swelling or pain when the ear is touched
- Loss of balance or walking in circles (in severe inner ear infections)
Common causes
- Floppy ears that restrict airflow (Cocker Spaniels, Basset Hounds, Labrador Retrievers)
- Water in the ear after swimming or bathing
- Allergies (food or environmental) — the most common underlying cause of chronic ear infections
- Ear mites — particularly common in puppies and dogs with outdoor access
- Foreign bodies (grass awns)
- Hormonal conditions (hypothyroidism)
What to do
A single ear infection requires a vet visit for diagnosis and appropriate medication (antibiotic drops, antifungal drops or a combination). Do not treat at home with human ear drops or cotton buds — you risk pushing debris deeper and causing damage. If your dog has recurrent ear infections, work with your vet to identify and address the underlying cause — usually allergies.
2. Dental Disease (Periodontal Disease)
What it is
Dental disease is the most common health condition in adult dogs — affecting an estimated 80% of dogs over the age of three. It begins with plaque build-up on tooth surfaces, hardens into tartar, and progresses to gingivitis, periodontal disease and eventually tooth loss. Beyond the mouth, severe dental disease has been linked to heart, kidney and liver problems caused by bacteria entering the bloodstream.
Symptoms to watch for
- Bad breath (halitosis) — the most common early sign
- Yellow or brown tartar build-up on teeth, especially the back molars
- Red, swollen or bleeding gums
- Reluctance to eat hard food or chew toys
- Drooling more than usual
- Pawing at the mouth or face
- Dropping food while eating
Prevention and treatment
- Daily tooth brushing with dog-specific toothpaste is the single most effective preventive measure
- Raw meaty bones (appropriately sized) provide significant mechanical cleaning
- Dental chews with the VOHC (Veterinary Oral Health Council) seal have proven efficacy
- Professional dental scaling under anaesthetic at the vet — necessary once tartar has hardened
If your dog has never had dental care and is over three years old, schedule a dental examination at your vet. Many dogs require a professional clean before home prevention can be effectively maintained.
3. Skin Allergies (Canine Atopic Dermatitis)
What it is
Allergies are one of the most frustrating and most common health challenges in modern dogs. Canine atopic dermatitis — an inherited predisposition to develop allergic reactions to environmental allergens (pollen, dust mites, mould, grasses) — affects an estimated 10–15% of the dog population. Food allergies, while less common, also cause significant skin and gastrointestinal symptoms.
Symptoms to watch for
- Persistent itching — particularly of the paws, face, armpits, groin and ears
- Repetitive paw licking (often staining the fur between the toes rust-red)
- Recurrent ear infections
- Hot spots (acute moist dermatitis) — inflamed, weeping patches of skin
- Hair loss from repeated scratching
- Skin thickening and darkening in chronic cases
- Gastrointestinal symptoms (vomiting, diarrhoea) more commonly associated with food allergies
Breeds most commonly affected
West Highland White Terriers, Bulldogs, French Bulldogs, Labrador Retrievers, Golden Retrievers, German Shepherds, Boxers, Pugs and Cocker Spaniels are among the most commonly affected breeds.
Treatment
Allergy management is rarely a one-step fix. It typically involves a combination of:
- Identifying and reducing allergen exposure where possible
- Medicated shampoos and skin barrier support (omega fatty acid supplementation)
- Anti-itch medications: apoquel (oclacitinib), cytopoint (lokivetmab) or in some cases steroids
- Allergen-specific immunotherapy (desensitisation injections) for long-term management
- Elimination diet trials (8–12 weeks minimum) to diagnose food allergies
Work with a veterinary dermatologist if your dog's allergies are severe or unresponsive to initial treatment.
4. Obesity
What it is
Canine obesity has reached epidemic proportions. Studies suggest that over 50% of dogs in developed countries are overweight or obese. Obesity is not simply a cosmetic issue — it is a serious medical condition that contributes to diabetes, joint disease, heart disease, respiratory problems, reduced immune function and a significantly shortened lifespan. An obese dog lives, on average, 2.5 years less than a dog at a healthy weight.
How to assess your dog's weight
Use the Body Condition Score (BCS) rather than relying on weight alone, since ideal weight varies enormously between breeds and individuals:
- Healthy weight: Ribs easily felt but not visible; waist visible from above; abdomen tucked up from the side
- Overweight: Ribs felt only with firm pressure; no visible waist; abdomen flat or rounded
- Obese: Ribs cannot be felt; no waist definition; abdomen distended; fat deposits over spine and base of tail
Causes
- Overfeeding — often dramatically underestimating calorie content of food and treats
- Insufficient exercise
- Neutering (reduces metabolic rate by approximately 20–30% in many dogs)
- Hypothyroidism — always worth ruling out in a dog who gains weight despite controlled diet
- High-calorie commercial treats given in excess
Treatment
Weight loss in dogs requires a caloric deficit — ideally under veterinary supervision. Key steps:
- Weigh food precisely with kitchen scales — never use volume measures
- Switch to a lower-calorie, higher-fibre food formulated for weight management
- Count treats in the daily calorie total — treats should be no more than 10% of daily calories
- Increase exercise gradually (avoid sudden intensive exercise in obese dogs — joint risk)
- Schedule monthly weigh-ins at the vet to track progress
5. Arthritis (Osteoarthritis)
What it is
Arthritis is the progressive degeneration of joint cartilage. It is extremely common in older dogs and in large breeds — affecting an estimated 80% of dogs over the age of eight. It is chronically under-diagnosed because dogs instinctively hide pain and because owners often attribute the signs to "just getting old."
Symptoms to watch for
- Stiffness after rest, especially in the morning — improving with gentle movement
- Reluctance to climb stairs, jump into the car or onto furniture they previously enjoyed
- Slowing down on walks or refusing to walk as far as before
- Difficulty standing up from a lying position
- Licking or chewing at a specific joint
- Muscle loss over the hindquarters
- Behavioural changes: increased irritability or aggression when touched in a painful area
Management
Arthritis cannot be cured, but it can be managed effectively to maintain quality of life:
- Weight management — the single most impactful intervention; every kilogram removed reduces joint load significantly
- Controlled, regular exercise — short, frequent walks on soft surfaces; swimming is excellent
- Joint supplements — omega-3 fatty acids (fish oil), glucosamine and chondroitin have supporting evidence
- NSAIDs (non-steroidal anti-inflammatory drugs) prescribed by a vet — highly effective for pain management with appropriate monitoring
- Physiotherapy and hydrotherapy — increasingly available and evidence-based
- Environmental modifications — ramps instead of stairs, orthopedic beds, non-slip surfaces
6. Fleas, Ticks and Parasites
What it is
External parasites — fleas, ticks and mange mites — are among the most common reasons dogs visit the vet. They cause intense discomfort, skin damage and can transmit serious diseases. The frustrating reality: if you see one flea on your dog, there are likely hundreds more in your home environment — fleas spend only a fraction of their life on the animal.
Fleas: symptoms and treatment
- Symptoms: Intense scratching especially around the base of the tail; visible small dark insects moving through the coat; "flea dirt" (tiny black specks that turn red when wet — flea faeces containing digested blood)
- Treatment: Prescription flea treatment on the dog AND environmental treatment (house spray, washing all bedding at 60°C). Over-the-counter products are far less effective than prescription treatments from your vet.
Ticks: symptoms and treatment
- Symptoms: A tick appears as a small, round, dark lump on the skin — often found around the head, neck, ears and between the toes after walks in long grass or woodland
- Treatment: Remove with a specialist tick hook (never squeeze, burn or cover with petroleum jelly). Monitor the bite site and your dog's health for 2–3 weeks — ticks can transmit Lyme disease, babesiosis and other serious conditions. Year-round tick prevention is strongly recommended for dogs with woodland or field access.
Intestinal worms
Roundworms, tapeworms, hookworms and whipworms are common intestinal parasites. Regular worming — every 1–3 months depending on lifestyle and risk — is essential. Some worms (particularly roundworms) are transmissible to humans, making treatment a public health matter as well as an animal welfare one.
7. Diarrhoea and Vomiting
What it is
Gastrointestinal upset is one of the most common reasons dogs visit the vet. Most cases of acute diarrhoea or vomiting are self-limiting — caused by dietary indiscretion (eating something they shouldn't), a sudden diet change or a mild infection — and resolve within 24–48 hours.
When to manage at home
A single episode of vomiting or 1–2 bouts of soft stool in an otherwise bright, alert, hydrated adult dog can typically be monitored at home:
- Withhold food for 12 hours (not water)
- Reintroduce a bland diet: boiled chicken and white rice in small, frequent meals for 2–3 days
- Ensure adequate water intake to prevent dehydration
- Gradually transition back to normal food over 3–4 days
When to see a vet immediately
- Blood in vomit or diarrhoea
- Vomiting more than 3–4 times in a 24-hour period
- Signs of pain, lethargy or weakness alongside GI symptoms
- A swollen or distended abdomen — this can indicate bloat (GDV), a life-threatening emergency
- Puppies, elderly dogs or dogs with known health conditions — these patients dehydrate and decline faster
- Suspected ingestion of a toxin, foreign body or medication
8. Kennel Cough (Infectious Tracheobronchitis)
What it is
Kennel cough is a highly contagious respiratory infection — caused by a combination of viruses and bacteria, most commonly Bordetella bronchiseptica and parainfluenza virus. It spreads rapidly wherever dogs congregate: kennels, dog parks, training classes, grooming salons and vet waiting rooms.
Symptoms to watch for
- A harsh, dry, honking cough — often described as sounding like something stuck in the throat
- Retching or producing white foam after coughing bouts
- The dog otherwise remains bright, alert and eating normally in mild cases
- In severe cases: lethargy, loss of appetite, nasal discharge and fever — indicating possible pneumonia
Treatment and prevention
- Mild uncomplicated cases often resolve without treatment in 1–3 weeks with rest and reduced exercise
- Antibiotics may be prescribed if bacterial infection is severe or the dog is at risk
- Cough suppressants can provide comfort
- Prevention: The Bordetella vaccine (kennel cough vaccine) significantly reduces the severity and likelihood of infection — required by most kennels and recommended for any dog with regular social contact
9. Urinary Tract Infections (UTIs)
What it is
Bacterial infection of the bladder (cystitis) or urethra is particularly common in female dogs due to their shorter urethra. UTIs are uncomfortable, can ascend to the kidneys if untreated and sometimes trigger serious complications in dogs with underlying conditions.
Symptoms to watch for
- Urinating much more frequently than usual
- Straining to urinate, producing only a few drops
- Blood in the urine (pink, red or brown discolouration)
- Licking at the genitals excessively
- Urinating indoors despite being housetrained
- Crying or showing discomfort while urinating
Treatment
UTIs require a vet visit and urine analysis. Antibiotics are typically prescribed for 7–14 days. Do not wait and see with suspected UTIs — a simple bladder infection can progress to a kidney infection (pyelonephritis) rapidly and cause serious lasting damage. In male dogs especially, difficulty urinating is a medical emergency requiring immediate attention.
10. Hip Dysplasia
What it is
Hip dysplasia is an inherited developmental abnormality in which the ball and socket of the hip joint do not fit together properly, causing instability, painful wear and eventually severe arthritis. It is particularly common in large and giant breeds: German Shepherds, Labrador Retrievers, Golden Retrievers, Rottweilers and Great Danes.
Symptoms to watch for
- Difficulty rising from lying down
- "Bunny hopping" gait — moving both hind legs together when running
- Swaying hindquarters
- Reduced activity and reluctance to exercise
- Hind limb muscle wasting
- Pain when hips are manipulated
Management
Depending on severity and age, treatment ranges from lifelong medical management to surgical intervention:
- Medical management: weight control, physiotherapy, anti-inflammatory medication, joint supplements
- Surgical options: triple pelvic osteotomy (TPO) in young dogs with good cartilage; total hip replacement (THR) — the most effective long-term solution; femoral head and neck excision (FHO) for smaller dogs
Prevention: Always buy large-breed puppies from breeders who health-test parents for hip dysplasia (BVA/KC Hip Scheme in the UK; OFA in the USA). Avoid over-exercising large breed puppies during their growth phase.
11. Bloat (Gastric Dilatation-Volvulus — GDV)
What it is
GDV is a true veterinary emergency — one of the most rapidly fatal conditions in dogs. The stomach fills with gas and then rotates on its axis, trapping the gas and cutting off blood supply to major organs. Without emergency surgery, most dogs with GDV die within hours.
It most commonly affects large, deep-chested breeds: Great Danes, German Shepherds, Weimaraners, Dobermanns, Standard Poodles, Irish Setters and Boxers.
Symptoms — know these by heart
- Distended, hard, painful abdomen — often visibly swollen
- Unproductive retching — attempting to vomit but producing nothing or only white foam
- Restlessness and inability to get comfortable
- Excessive drooling
- Pale gums
- Rapid deterioration into collapse and shock
If you see these signs, go to an emergency vet immediately. Do not wait. Do not call and wait for a callback. Drive directly to the nearest emergency clinic. Every minute counts.
Risk reduction
- Feed large dogs two or three smaller meals rather than one large daily meal
- Avoid vigorous exercise for 1–2 hours before and after eating
- Avoid raised food bowls (despite historic advice, current evidence does not support them for GDV prevention)
- Consider prophylactic gastropexy (surgical stomach tacking) in high-risk breeds — discuss with your vet
12. Cancer
What it is
Cancer is the leading cause of death in dogs over the age of ten, accounting for nearly half of all deaths in dogs over two years in some studies. The good news is that many canine cancers are treatable — and some are curable — when caught early. The key is knowing what to look for and examining your dog regularly.
Warning signs to watch for
- Any lump or bump that was not there before, or that is growing
- A sore that does not heal within 2 weeks
- Unexplained weight loss
- Loss of appetite
- Bleeding or discharge from any body opening
- Difficulty breathing, urinating or defecating
- Persistent lameness or stiffness
- Offensive odour despite normal hygiene
What to do
Perform a monthly head-to-tail check on your dog: run your hands over their entire body feeling for lumps, bumps and areas of sensitivity. Any new lump should be assessed by a vet — many are benign fatty lipomas, but some require urgent attention.
Annual or biannual vet check-ups from middle age onward are strongly recommended. Blood tests and imaging at these check-ups can detect internal tumours before they become symptomatic.
Building Your Dog's Health Defence: Essential Preventive Care
Prevention is always better — and cheaper — than treatment. These are the most impactful preventive measures every dog owner should maintain:
- Annual or biannual veterinary check-ups — from middle age onward
- Up-to-date vaccinations — core vaccines (distemper, parvovirus, hepatitis, leptospirosis) and lifestyle vaccines (kennel cough, rabies where required)
- Year-round flea, tick and worm prevention — appropriate to your dog's lifestyle and geographic area
- Daily tooth brushing or regular dental care
- Maintaining a healthy body weight
- Regular, age-appropriate exercise
- Monthly body checks at home
- Pet insurance — vet costs for serious illness or injury can run into thousands; insurance provides peace of mind and ensures you can always say yes to treatment
Final Thoughts
You are your dog's first line of defence. No one spends more time with your dog than you do, which means no one is better positioned to notice the first subtle signs that something is wrong. Trust your instincts — if your dog seems "off" even if you cannot pinpoint exactly why, a vet call or visit is always worth it.
Early detection, consistent preventive care and a good relationship with a trusted vet are the three things that will give your dog the longest, healthiest and happiest life possible. They cannot advocate for themselves. You can.
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