Cavalier King Charles Spaniel Breed Guide — Health Risks Explained
The Cavalier King Charles Spaniel consistently ranks among the most popular companion breeds in the United Kingdom, and it is not difficult to understand why. Exceptionally gentle, deeply affectionate, and patient with children, the Cavalier is, in many respects, close to the ideal family dog. Yet the breed also carries a cluster of inherited health conditions — some of them severe — that prospective owners must understand before purchasing a puppy. This guide provides a thorough and honest account of what the Cavalier is, what it needs, and what health tests responsible breeders should be conducting.
Origins and History
The history of the King Charles Spaniel type extends back to the Tudor and Stuart courts, where small, flat-faced toy spaniels were fashionable companions. The modern Cavalier King Charles Spaniel, however, is essentially a 20th-century creation. In the 1920s, American enthusiast Roswell Eldridge offered prize money at Crufts for breeders who could produce toy spaniels resembling those in old paintings by Van Dyck — dogs with longer muzzles, flatter skulls, and a more pointed nose than the heavily brachycephalic King Charles Spaniel that had become the show standard. The Cavalier King Charles Spaniel Club was founded in 1928, and the Kennel Club granted the breed separate registration in 1945. The Cavalier is classified under FCI Group 9. Breed clubs in Europe include the Cavalier King Charles Spaniel Club Germany, which promotes the breed's health scheme participation.
Temperament
The Cavalier is one of the gentlest and most people-oriented breeds in existence. It was bred purely as a companion and retains that purpose with great commitment — it thrives on human contact, dislikes being left alone, and is happiest when physically close to its family. The breed is typically good with strangers, children, other dogs, and even cats. It is not a guard dog and rarely displays aggression. The Cavalier is an excellent choice for first-time owners in terms of temperament and trainability, but only when purchased from health-tested parents — a caveat that cannot be overstated.
Size and Physical Characteristics
Cavaliers are a small to medium toy breed, typically weighing between 5 and 8 kg and standing around 30 to 33 cm at the shoulder. The coat is silky and moderately long, with feathering on the ears, legs, feet, and tail. The four recognised colour varieties are Blenheim (chestnut and white), tricolour (black, white, and tan), ruby (rich red), and black and tan. The Cavalier's face is relatively longer than that of the King Charles Spaniel, with a gentle, melting expression that has contributed enormously to the breed's appeal.
Key Health Conditions
Chiari-like Malformation and Syringomyelia (CM/SM)
Chiari-like Malformation (CM) is a structural condition in which the back of the skull is too small to comfortably accommodate the brain. The overcrowding pushes brain tissue towards the foramen magnum — the opening at the base of the skull through which the spinal cord passes — obstructing the normal flow of cerebrospinal fluid. This obstruction can cause fluid-filled cavities called syrinxes to form within the spinal cord, a condition known as Syringomyelia (SM). The combination is abbreviated CM/SM and is widespread in the Cavalier breed.
The most characteristic symptom of CM/SM is phantom scratching — the dog scratches repeatedly at the air near its ear, neck, or shoulder without making contact with the skin. This occurs because the syrinx disrupts sensory nerve signals, creating an abnormal sensation that the dog attempts to relieve. Other symptoms include neck or shoulder pain (the dog may cry when touched or lifted under the arms), apparent sensitivity to the collar, reluctance to exercise, scoliosis (curvature of the spine), and in severe cases, weakness or paralysis of the hindlimbs. Some dogs with SM on MRI scanning show no clinical signs at all, while others are significantly affected.
SM is graded from 0 (no syrinx) to 5 (severe syrinx with significant cord damage) on the BVA/KC MRI Scheme. Dogs used for breeding should be MRI scanned and graded under this scheme, with preference given to clear or minimally affected animals. The Cavalier King Charles Spaniel Club Health Scheme and Breeding Protocol recommends that both parents are MRI scanned before a litter is produced, and that results are available for prospective buyers to examine. Treatment for affected dogs may include medication to reduce cerebrospinal fluid production, pain management, or in severe cases, surgical decompression of the skull.
Mitral Valve Disease (MVD)
Mitral Valve Disease is the most common cause of death in the Cavalier King Charles Spaniel. Research suggests that approximately 50 per cent of Cavaliers have a detectable heart murmur by the age of five, and by the age of ten, that figure rises to approximately 80 per cent. The mitral valve — one of the four valves in the heart — degenerates over time, allowing blood to leak backwards with each heartbeat. A veterinarian can detect this as a heart murmur during auscultation. As the valve deteriorates further, the heart must work progressively harder to maintain circulation, eventually leading to congestive heart failure.
Signs of advancing heart disease include exercise intolerance, coughing (particularly at night or after rest), breathlessness, and in advanced stages, fluid accumulation in the lungs. Modern medications — including pimobendan, ACE inhibitors, and diuretics — can significantly slow the progression of disease and improve quality and length of life when started at the appropriate stage. Regular cardiac monitoring by a veterinary cardiologist is strongly recommended for all Cavaliers from the age of approximately one year.
The BVA/KC Heart Scheme, together with the Cavalier King Charles Spaniel Club Breeding Protocol, recommends that dogs are not used for breeding unless they are free of heart murmur at the age of 2.5 years, and that both parents were free of murmur at the age of five years. This protocol is designed to delay the age of onset of MVD in the breed population. Buyers must request documentation confirming that both parents have been heart-checked in accordance with this protocol. A breeder who cannot provide these certificates should not be trusted.
Episodic Falling Syndrome (EFS)
Episodic Falling Syndrome is a paroxysmal dyskinesia — a movement disorder — in which affected Cavaliers experience sudden episodes of muscle stiffness, collapse, and an inability to relax muscle tone, typically triggered by exercise or excitement. During an episode, the dog's limbs may be held rigidly in extension and the back may arch. Episodes last from a few seconds to several minutes. The dog remains conscious throughout and recovers spontaneously. EFS is distinct from epilepsy, though it may superficially resemble a seizure. A DNA test for EFS is available through several accredited laboratories. Responsible breeders test both parents and can provide certificates confirming that puppies will not be affected.
Curly Coat and Dry Eye Syndrome (CC/DE)
Curly Coat and Dry Eye Syndrome is a combined condition in which affected puppies develop a curly, rough coat (different from the normal Cavalier silky coat) and keratoconjunctivitis sicca (insufficient tear production), leading to chronic dry, painful eyes. The condition is present from birth and is caused by a recessive genetic mutation. A DNA test is available, and responsible breeders test both parents before breeding. Carriers can be used in breeding programmes provided they are mated only with clear dogs, ensuring that no affected puppies can be produced.
Eye Conditions
Cavaliers are also susceptible to keratoconjunctivitis sicca (dry eye disease) outside the context of CC/DE, as well as retinal conditions including multifocal retinal dysplasia. Annual eye examination under the BVA/KC Eye Scheme is recommended for breeding stock. Eye conditions affecting vision or comfort should be excluded from breeding lines.
Grooming
The Cavalier's silky coat requires brushing two to three times weekly to prevent tangles, with particular attention to the ear feathering and the fur between the toes. The long, feathered ears should be checked and cleaned regularly, as the pendulous ear flap restricts airflow and creates a warm, moist environment conducive to ear infections. Routine care also includes dental hygiene, nail trimming, and checking the skin folds around the face.
Exercise Needs
Cavaliers require moderate daily exercise — around 40 to 60 minutes — and generally adapt their energy level to their household. They enjoy walks, play sessions, and gentle off-lead runs but are not demanding in the way that working terrier or herding breeds can be. The breed is suitable for older owners and those with less active lifestyles, provided basic exercise needs are met.
Is the Cavalier Right for You?
The Cavalier King Charles Spaniel can be a wonderful companion — gentle, adaptable, and deeply loving. However, given the severity and prevalence of CM/SM and mitral valve disease in the breed, purchasing a puppy without full health certification for both parents is strongly discouraged. Buyers should request BVA/KC Heart Scheme certificates confirming the parents meet the Cavalier Breeding Protocol cardiac criteria, MRI results for CM/SM grading, DNA test results for EFS and CC/DE, and current BVA eye scheme certificates. A breeder who provides all of these without hesitation is taking the breed's health seriously. One who cannot or will not should be avoided entirely.