Disease Library

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

505 results
skin

Feline Indolent Ulcer (Rodent Ulcer)

Another specific presentation within the Eosinophilic Granuloma Complex, causing a characteristic ulcerated lesion on the upper lip —…

infectious

Feline Infectious Peritonitis (FIP)

FIP is caused by a mutated form of a very common and usually harmless intestinal virus (feline coronavirus). In a small percentage of…

cancer

Feline Infiltrative Lipoma

A locally invasive variant of the common, typically benign lipoma (fatty tumor), genuinely uncommon in cats — unlike standard lipoma which…

digestive

Feline Inflammatory Bowel Disease

IBD is a chronic condition where the intestinal lining becomes persistently inflamed, causing ongoing vomiting, diarrhea, and/or weight…

ear

Feline Inflammatory Polyps (Aural Polyps)

Benign (non-cancerous) growths that develop within the ear canal or middle ear, often extending from the eustachian tube area — notably…

cancer

Feline Injection-Site Sarcoma (FISS)

An aggressive, locally invasive tumor that can develop at the site of a prior injection (historically most associated with certain…

emergency trauma

Feline Insect Sting Reaction (Bee/Wasp)

A reaction to a bee, wasp, or other stinging insect sting, ranging from a mild, localized swelling to a genuinely dangerous systemic…

endocrine

Feline Insulinoma

A rare tumor of the insulin-producing cells within the pancreas, causing inappropriate, excessive insulin release regardless of blood sugar…

parasitic

Feline Intestinal Helminth Infection (Roundworm, Tapeworm, Hookworm)

Intestinal worms — most commonly roundworms, tapeworms, and less often hookworms — are among the most common parasites affecting cats,…

digestive

Feline Intestinal Lymphangiectasia

A condition involving abnormal dilation of the lymphatic vessels within the intestinal wall, genuinely uncommon in cats and much more…

digestive

Feline Intussusception

A condition where one segment of intestine telescopes into an adjacent segment, similar to a collapsing telescope — this causes an…

eye

Feline Iris Coloboma

A congenital gap or defect in the iris (the colored part of the eye), genuinely uncommon and often causing minimal functional impact — this…

neurological

Feline Ischemic Encephalopathy

A sudden neurological condition resulting from an interruption of blood flow to part of the brain, historically associated in some regions…

infectious

Feline L-Form Bacterial Infection

A genuinely unusual bacterial infection where bacteria lacking their normal protective cell wall cause illness, most commonly following a…

respiratory

Feline Laryngeal Collapse

A condition where the structures of the larynx (voice box) lose normal support and partially collapse, causing airway obstruction — often…

respiratory

Feline Laryngeal Paralysis

A condition where the muscles controlling the larynx (voice box) fail to open normally during breathing, genuinely uncommon in cats…

musculoskeletal

Feline Legg-Calvé-Perthes Disease

A condition affecting the hip joint in young, growing cats, where the blood supply to the head of the femur (thigh bone) becomes disrupted,…

eye

Feline Lens Luxation

A displacement of the eye's lens from its normal position, either partially (subluxation) or completely (luxation) — can occur secondary to…

eye

Feline Lens-Induced Uveitis

A specific form of eye inflammation (uveitis) triggered by the body's immune response to lens proteins, most commonly following cataract…

infectious

Feline Leptospirosis

A bacterial infection much more extensively discussed and clinically significant in dogs, with cats generally considered more resistant to…

infectious

Feline Leukemia Virus (FeLV) infection

FeLV is a retrovirus that suppresses the immune system and can cause cancers (especially lymphoma) and severe anemia. It's one of the most…

poisoning toxicology

Feline Lilium spp. / Hemerocallis spp. toxicosis

Lily toxicity is one of the most severe and time-critical poisonings covered in this library — true lilies and daylilies are capable of…

poisoning toxicology

Feline Lily of the Valley Toxicosis

While true lilies (Lilium species) causing severe kidney injury are covered in their own entry, this addresses a botanically different…

skin

Feline Linear Granuloma

A third specific presentation within the Eosinophilic Granuloma Complex, causing a characteristic raised, linear (line-shaped) lesion most…