Pet health glossary

Activated charcoal

A vet-administered adsorbent that binds certain toxins in the gut, reducing absorption. Used selectively after some poisonings — not appropriate for every toxin or route of exposure.

Addison's disease(Hypoadrenocorticism)

Insufficient production of adrenal hormones, most often in young to middle-aged dogs. An Addisonian crisis causes collapse and is life-threatening.

Anaemia

Reduced red blood cells or haemoglobin, leading to poor oxygen delivery. Causes include blood loss, bone marrow disease, parasites and chronic illness.

Body condition score (BCS)

A hands-on scale (typically 1–9 for dogs and cats) used by vets to assess whether a pet is underweight, ideal or overweight. The ribs should be palpable with a light fat cover at ideal score.

Chronic kidney disease (CKD)(Chronic renal failure)

Progressive loss of kidney function, especially common in older cats. Staging (IRIS) guides diet, hydration support and medication to slow progression.

Cruciate ligament disease(CrCL tear)

Tear or rupture of the cranial cruciate ligament in the dog's knee, a common cause of sudden hind-limb lameness, especially in active or overweight dogs.

Cushing's disease(Hyperadrenocorticism)

Excess cortisol from adrenal or pituitary disease. Common in older dogs (pituitary form) and horses (PPID). Causes increased drinking, pot belly and skin changes.

Dental disease(Periodontal disease)

Plaque and tartar leading to gum inflammation, tooth loss and pain. Affects most cats over three years and many dogs; bad breath is an early sign.

Diabetes mellitus(Sugar diabetes)

A disorder of blood sugar regulation. Common in middle-aged, overweight cats (often linked to insulin resistance) and in dogs (often insulin-dependent).

Emesis(Induced vomiting)

Medically induced vomiting, sometimes used by vets to remove toxins from the stomach. Never induce vomiting at home unless your vet instructs you — some poisons cause more harm if vomited.

Feline lower urinary tract disease (FLUTD)(FLUTD)

A group of bladder and urethra conditions in cats, often stress-linked. Male cats with urethral blockage cannot pass urine — a life-threatening emergency.

Flea allergy dermatitis (FAD)(Flea bite hypersensitivity)

An allergic reaction to flea saliva — a single bite can trigger intense itching. Year-round flea control is essential even if fleas are not seen.

Flystrike(Myiasis)

When blowfly eggs hatch into maggots on a rabbit's skin, usually around the rear end in warm weather. Can become fatal within hours.

Gastric dilatation-volvulus (GDV)(Bloat)

A life-threatening dog emergency where the stomach fills with gas and may twist, cutting off blood supply. Large, deep-chested breeds are most at risk.

Heatstroke(Heat exhaustion)

Dangerous overheating when a pet cannot cool down — common in dogs exercised in heat, left in cars, or in poorly ventilated hutches. Can cause organ failure and death.

Hip dysplasia

Abnormal hip joint development in dogs, leading to arthritis and lameness. Large breeds are predisposed; screening schemes (BVA/KC) help responsible breeding.

Hyperthyroidism

Overactive thyroid glands in middle-aged and older cats, raising metabolism. Common signs include weight loss despite a good appetite.

Kennel cough(Canine infectious tracheobronchitis)

A highly contagious respiratory infection in dogs, spread in kennels, daycare and group walks. Usually self-limiting but can worsen in puppies or brachycephalic breeds.

Lungworm(Angiostrongylus vasorum)

A parasite spread by slugs and snails, endemic in parts of the UK. Can cause coughing, bleeding disorders and neurological signs in dogs.

Luxating patella(Slipping kneecap)

A condition where the kneecap slips out of its groove, common in small dogs. Graded I–IV by severity; higher grades often need surgery.

Myxomatosis

A viral disease of rabbits spread by biting insects and contact, often fatal without vaccination. Endemic in wild rabbits across the UK.

Obesity

Excess body fat harming health — around half of UK dogs and a quarter of cats are overweight per PDSA surveys. Linked to arthritis, diabetes and shorter lifespan.

Pancreatitis

Inflammation of the pancreas, often linked to high-fat meals in dogs. Can range from mild vomiting to severe, painful illness needing hospitalisation.

Parvovirus(Parvo)

A severe, contagious viral disease of dogs, especially unvaccinated puppies. Attacks the gut lining and immune system; hospitalisation is often required.

Pyometra(Uterine infection)

A life-threatening uterine infection in unspayed female dogs and cats, often developing weeks after a season. Open pyometra may show discharge; closed pyometra is especially dangerous.

Rabbit GI stasis(Gut stasis)

Slowing or stopping of the rabbit's digestive system, often triggered by pain, stress or low fibre intake. Rabbits must eat and pass droppings continuously.

Theobromine

A methylxanthine alkaloid in cocoa that dogs metabolise slowly. Dark and baking chocolate contain the most; toxicity is dose-dependent on weight and type.

Uveitis(Intraocular inflammation)

Inflammation inside the eye, painful in cats and dogs. Can be linked to infections, trauma, high blood pressure or immune disease.

Worming(Deworming)

Regular treatment against intestinal worms (and lungworm in dogs in risk areas). Puppies, kittens and hunting cats need more frequent schedules than adult indoor pets.

Xylitol

A sugar substitute highly toxic to dogs (and risky for cats). Causes rapid insulin release and can lead to liver failure — common in sugar-free gum, peanut butter and baked goods.