Disease Library

A comprehensive reference covering feline diseases across every major body system — causes, symptoms, diagnosis, treatment, and prevention.

505 results
endocrine

Feline Hungry Bone Syndrome

A genuinely notable complication that can occur following successful treatment of significant hyperparathyroidism, where blood calcium…

kidney

Feline Hydronephrosis

Dilation and swelling of the kidney's internal collecting structures caused by an obstruction to normal urine outflow, distinct from being…

endocrine

Feline Hyperadrenocorticism (Cushing's Disease)

A condition caused by excess cortisol production, genuinely much less commonly diagnosed in cats compared to dogs, where this condition is…

endocrine

Feline Hyperadrenocorticism (Cushing's Disease)

Feline hyperadrenocorticism (Cushing's disease) is a rare condition in cats — notably much less common than in dogs — caused by excess…

skin

Feline Hyperesthesia Syndrome

A genuinely puzzling condition causing episodes of skin rippling, tail chasing, and apparent skin sensitivity along the back, sometimes…

respiratory

Feline Hypersensitivity Pneumonitis

A genuinely uncommon condition where the lungs develop an exaggerated immune response to inhaled particles (such as certain mold spores or…

endocrine

Feline Hyperthyroidism

Hyperthyroidism is one of the most common hormonal disorders in older cats, caused by an overactive thyroid gland producing excess thyroid…

heart

Feline Hypertrophic Cardiomyopathy (HCM)

HCM is the most common heart disease in cats, causing the walls of the heart's main pumping chamber to thicken abnormally. Many affected…

endocrine

Feline Hypoadrenocorticism (Addison's Disease)

A condition caused by inadequate cortisol and, in many cases, aldosterone production from the adrenal glands, genuinely much less commonly…

endocrine

Feline Hypoadrenocorticism (Addison's Disease)

Hypoadrenocorticism, commonly called Addison's disease, is a rare condition in cats involving insufficient production of adrenal hormones…

endocrine

Feline Hypoglycemia (Low Blood Sugar)

Abnormally low blood glucose, which can result from various underlying causes rather than being a standalone diagnosis — genuinely…

neurological

Feline Hypokalemic Polymyopathy

A condition causing generalized muscle weakness resulting from low blood potassium levels, genuinely notable for a recognized association…

emergency trauma

Feline Hypothermia

A dangerous drop in body temperature below the normal feline range (roughly 100.5-102.5°F / 38-39.2°C), which impairs normal organ and…

endocrine

Feline Hypothyroidism

A deficiency of thyroid hormone, notably rare as a naturally-occurring condition in adult cats (in contrast to the much more commonly…

urinary

Feline Idiopathic Cystitis (FIC) / Feline Lower Urinary Tract Disease (FLUTD)

FIC is the most common cause of lower urinary tract signs in cats under 10 years old, and involves bladder inflammation without an…

skin

Feline Idiopathic Facial Dermatitis (Black Face Disease)

A condition causing significant black, greasy discharge accumulation on the face, particularly around the chin, lips, and eye area, along…

skin

Feline Idiopathic Facial Dermatitis (Detailed Management Considerations)

While Idiopathic Facial Dermatitis (Black Face Disease) is covered in its own entry, this addresses detailed, practical management…

endocrine

Feline Idiopathic Hypercalcemia

Elevated blood calcium without an identifiable underlying cause despite thorough investigation — genuinely increasingly recognized in cats,…

digestive

Feline Idiopathic Megacolon

While constipation-megacolon is discussed generally in its own entry, this addresses the specific idiopathic form — where the colon becomes…

digestive

Feline Idiopathic Megacolon (severe/refractory)

While Constipation and Megacolon are covered together in an earlier entry, this addresses the more severe, refractory end of that spectrum…

respiratory

Feline Idiopathic Pulmonary Fibrosis

A progressive scarring process affecting lung tissue, genuinely uncommon in cats and much more extensively documented in humans and certain…

kidney

Feline Idiopathic Renal Hematuria

A rare condition where a kidney bleeds spontaneously without an identifiable underlying cause (like a stone, tumor, or infection) despite…

neurological

Feline Idiopathic Tremor Syndrome

A condition causing generalized body tremors without an identifiable specific underlying cause despite thorough investigation — genuinely…

infectious

Feline Immunodeficiency Virus (FIV) infection

FIV is a retrovirus (in the same family as human HIV, though it does not infect humans) that gradually weakens a cat's immune system over…