Cavalier King Charles Spaniel: inherited diseases and health

Updated 2026-09-30 · 3 sources

Based on: OMIA (University of Sydney), Science for Animal Welfare (UFAW), Wikidata

Breed health

The inherited conditions below have been documented in this breed in published research. That does not mean your dog has them or will get them – but it helps to know the names when you talk to a breeder or a vet.

Conditions this breed is prone to

Veterinary charities list this breed as more likely than others to get these conditions. Read the signs and what to do:

Cavalier King Charles Spaniel and chocolate: how much is dangerous?

Typical adult weight: 6.7 kg. Grams of chocolate at which signs can start (20 mg/kg) and at which severe signs are reported (40 mg/kg):

Dog weight	Milk	Dark 70–85%	Baking / unsweetened
6.7 kg	67 g signs 134 g severe	17 g signs 34 g severe	9.6 g signs 19 g severe

Based on published doses: signs from about 20 mg/kg, severe signs from 40 mg/kg (US FDA, Cortinovis & Caloni 2016, Swedish Poison Information Centre). An estimate, not a diagnosis.

Check the exact amount with the chocolate calculator →

Inherited conditions documented in the breed

Conditions documented: 26

A gene variant is known for 11 of the conditions below, so a DNA test may exist. Ask your vet or the breed club.

Condition	Body system	Inheritance	Gene variant known
Acyl-CoA dehydrogenase, medium chain, deficiency of^[1]	Nervous system	Autosomal recessive	Yes
Budd-chiari syndrome^[1]	Cardiovascular system	–	–
Chiari malformation Type I with syringomyelia^[1]	Nervous system	Multifactorial	No
Congenital keratoconjunctivitis sicca and ichthyosiform dermatosis^[1]	Vision / eye	Autosomal recessive	Yes
Congenital Keratoconjunctivitis Sicca and Ichthyosiform Dermatosis^[2]	–	–	–
Degenerative myelopathy^[1]	Nervous system	Autosomal recessive	Yes
Episodic falling, BCAN-related^[1]	Nervous system	Autosomal recessive	Yes
Immunodeficiency, CARMIL2-related^[1]	Respiratory system	–	Yes
Intervertebral disc disease, predisposition to^[1]	Skeleton (incl. short stature & teeth)	Autosomal dominant	Yes
Menkes disease^[1]	Liver/biliary system	X-linked recessive	Yes
Mitral Valve Disease (MVD)^[2]	–	–	–
Multiple ocular defects^[1]	Vision / eye	–	–
Muscular dystrophy^[1]	Muscle	–	–
Muscular dystrophy, Duchenne type^[1]	Muscle	X-linked recessive	Yes
Myxomatous valvular degeneration^[1]	Cardiovascular system	Multifactorial	No
Otitis Externa^[2]	–	–	–
Pancreatitis^[2]	–	–	–
Patellar Luxation^[2]	–	–	–
Primary Secretory Otitis Media^[2]	–	–	–
Renal dysplasia^[1]	Renal / urinary system	–	–
Retinal dysplasia^[1]	Vision / eye	–	–
Syringomyelia^[1]	Nervous system	Multifactorial	No
Syringomyelia^[2]	–	–	–
Thrombocytopenia, TUBB1-related^[1]	Haematopoietic system	Autosomal recessive	Yes
Wilson disease^[1]	Liver/biliary system	Autosomal recessive	Yes
Xanthinuria, type II^[1]	Renal / urinary system	Autosomal recessive	Yes

What this list means

“Documented in the breed” means at least one published case or study – it says nothing about how common the condition is.
Many of these conditions are rare. A responsible breeder can tell you which health tests the parents have had.
Where the gene variant is known, a DNA test may exist – ask your vet or the breed club.
If your pet shows signs of illness, contact your vet. This page cannot tell you whether your pet is ill.

About the breed

Origin: United Kingdom
Height: 31.5 cm
Weight: 6.7 kg
FCI number: 136

^[3]

If your pet is struggling to breathe, has collapsed, is having a seizure or can't stand up: go to the nearest vet now.

Not sure how serious it is?

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Sources

How this page was made: the list is taken directly from the sources below; nothing on it was written by AI. Names of conditions may be machine-translated. It is information, not a diagnosis. How we write our pages