Cat Symptom Reference Guide

Cats are masters at hiding illness, making it crucial to recognize subtle signs of health problems. This guide helps you identify common symptoms, understand their potential causes, and know when to seek veterinary care.

Digestive Symptoms

Vomiting

Occasional vomiting (once every few weeks) may be normal, but frequent vomiting warrants investigation.

• Possible causes: Hairballs, eating too fast, food intolerance, intestinal parasites, kidney disease, hyperthyroidism, inflammatory bowel disease, pancreatitis, obstruction, poisoning
• When to worry: Vomiting more than 2-3 times in 24 hours, blood in vomit, vomiting with lethargy or loss of appetite, repeated dry heaving, vomiting immediately after every meal
• Urgency: Schedule same-day vet visit if vomiting is frequent or accompanied by other symptoms

Diarrhea

• Possible causes: Dietary change, food intolerance, parasites, infections, inflammatory bowel disease, stress, medication side effects, cancer
• When to worry: Blood or mucus in stool, black tarry stool, diarrhea lasting more than 24 hours, accompanied by vomiting or lethargy, very watery or explosive diarrhea
• Urgency: Kittens and senior cats need prompt attention; healthy adults can wait 24 hours if otherwise normal

Constipation

• Possible causes: Dehydration, low fiber diet, hairballs, megacolon, pelvic injury, neurological issues, obstruction
• Signs: Straining in litter box, small hard stools, crying during defecation, reduced or absent bowel movements
• When to worry: No bowel movement in 48+ hours, straining with no result, loss of appetite, vomiting

Loss of Appetite

• Possible causes: Dental pain, nausea, stress, upper respiratory infection, kidney disease, liver disease, cancer, medication side effects
• When to worry: Complete food refusal for more than 24-48 hours (cats can develop hepatic lipidosis from not eating)
• Urgency: Cats should never go more than 2-3 days without food; seek veterinary care promptly

Urinary Symptoms

Increased Urination (Polyuria)

• Possible causes: Diabetes, kidney disease, hyperthyroidism, urinary tract infection, liver disease
• Often accompanied by: Increased thirst, weight changes, increased appetite
• Urgency: Schedule veterinary appointment within a few days; bring a urine sample if possible

Straining to Urinate or Urinary Blockage

• Possible causes: Urinary crystals or stones, urinary tract infection, feline lower urinary tract disease (FLUTD), urethral obstruction
• Signs: Frequent trips to litter box, producing small amounts or nothing, crying while urinating, blood in urine, licking genital area
• Urgency: EMERGENCY for male cats — urinary blockage can be fatal within 24-48 hours

Blood in Urine (Hematuria)

• Possible causes: Urinary tract infection, bladder stones, FLUTD, bladder cancer, trauma
• Urgency: Same-day veterinary visit recommended; emergency if cat cannot urinate

Respiratory Symptoms

Sneezing and Nasal Discharge

• Possible causes: Upper respiratory infection (cat cold), allergies, dental disease, nasal polyps, foreign object, herpesvirus carrier
• When to worry: Green or yellow discharge, difficulty breathing, loss of appetite, eye involvement, lasting more than 7-10 days
• Urgency: Mild sneezing can wait a few days; difficulty breathing is an emergency

Coughing

• Possible causes: Asthma, heartworm disease, respiratory infection, heart disease, lungworm, hairballs (often confused with coughing)
• When to worry: Persistent coughing, coughing with difficulty breathing, coughing blood
• Urgency: Any coughing in cats should be evaluated, as it's less common than in dogs

Difficulty Breathing

• Possible causes: Asthma, heart disease, pleural effusion, pneumonia, trauma, allergic reaction
• Signs: Open-mouth breathing, rapid breathing, extended neck, blue or gray gums, belly breathing
• Urgency: EMERGENCY — cats normally breathe with mouth closed; open-mouth breathing indicates severe distress

Skin and Coat Symptoms

Excessive Scratching or Hair Loss

• Possible causes: Fleas, food allergies, environmental allergies, ringworm, mites, stress (psychogenic alopecia), hyperthyroidism
• When to worry: Open sores, spreading bald patches, skin redness or scaling, excessive grooming leading to skin damage
• Urgency: Schedule appointment within 1-2 weeks unless severe

Lumps and Bumps

• Possible causes: Lipomas (fatty tumors), cysts, abscesses, injection site reactions, cancer
• When to worry: Rapid growth, changes in size or shape, ulceration, location on mammary chain (high cancer risk)
• Urgency: Any new lump should be evaluated; mammary lumps need prompt attention

Wounds and Abscesses

• Common in: Outdoor cats and those in multi-cat households with conflict
• Signs of abscess: Swelling, warmth, pain, fever, possible foul-smelling discharge
• Urgency: Seek veterinary care within 1-2 days; sooner if cat is lethargic or feverish

Eye Symptoms

Eye Discharge

• Clear discharge: May be normal or indicate allergies, blocked tear duct
• Yellow/green discharge: Suggests infection, often with upper respiratory illness
• Red/brown staining: Usually cosmetic (tear staining) but can indicate chronic irritation

Squinting, Pawing at Eye, or Eye Held Closed

• Possible causes: Corneal ulcer, foreign object, conjunctivitis, glaucoma, uveitis
• Urgency: Same-day veterinary care — eye problems can worsen rapidly

Cloudiness, Color Change, or Pupil Abnormality

• Possible causes: Cataracts, glaucoma, uveitis, hypertension, cancer
• Urgency: Prompt veterinary evaluation needed; some conditions cause rapid vision loss

Ear Symptoms

Head Shaking or Ear Scratching

• Possible causes: Ear mites (especially in kittens), ear infection, allergies, polyps, foreign object
• Signs: Dark discharge, odor, redness, swelling, pain when ears are touched
• Urgency: Schedule appointment within 1 week; sooner if cat is in obvious distress

Behavioral and Neurological Symptoms

Lethargy

• Possible causes: Infection, pain, anemia, organ disease, cancer, depression
• When to worry: Sudden onset, accompanied by loss of appetite, hiding, or other symptoms
• Urgency: If severe or sudden, seek same-day care; gradual onset can wait 1-2 days

Hiding

• Possible causes: Pain, illness, stress, fear, cognitive dysfunction in seniors
• When to worry: Sudden change in normally social cat, accompanied by other symptoms
• Urgency: Evaluate for other symptoms; cats often hide when seriously ill

Increased Vocalization

• Possible causes: Pain, hyperthyroidism, cognitive dysfunction, hearing loss, attention-seeking, mating behavior
• When to worry: Sudden increase, especially at night, accompanied by other symptoms
• Urgency: Schedule vet visit within 1-2 weeks if no emergency symptoms present

Seizures

• Possible causes: Epilepsy, toxin ingestion, brain tumor, liver disease, low blood sugar, infections
• During a seizure: Keep cat safe from falling, don't restrain or put hands near mouth, time the seizure
• Urgency: EMERGENCY if first seizure, seizure lasting more than 2-3 minutes, or multiple seizures in 24 hours

Loss of Balance or Coordination

• Possible causes: Vestibular disease, ear infection, stroke, brain tumor, toxicity
• Signs: Head tilt, falling, circling, rapid eye movement (nystagmus), unsteady gait
• Urgency: Same-day veterinary evaluation needed

Weight and Appetite Changes

Weight Loss

• Possible causes: Hyperthyroidism, diabetes, kidney disease, cancer, dental disease, parasites, inflammatory bowel disease
• When to worry: Loss of more than 5% of body weight, visible spine or hip bones
• Urgency: Schedule appointment within 1 week for unexplained weight loss

Increased Appetite with Weight Loss

• Highly suggestive of: Hyperthyroidism or diabetes
• Urgency: Schedule appointment within 1 week

Increased Thirst

• Possible causes: Diabetes, kidney disease, hyperthyroidism, liver disease
• Normal water intake: About 1 ounce per pound of body weight daily (more on wet food diet, less on dry)
• Urgency: Schedule appointment within 1-2 weeks; bring urine sample if possible

Pain Indicators in Cats

Cats instinctively hide pain. Learn to recognize these subtle signs:

Behavioral Signs of Pain

• Hiding or withdrawing
• Reduced activity or reluctance to jump
• Decreased grooming or over-grooming one area
• Aggression when touched
• Loss of appetite
• Avoiding the litter box
• Personality changes

Physical Signs of Pain

• Tense facial expression, squinting
• Flattened ears
• Hunched posture
• Rapid, shallow breathing
• Elevated heart rate
• Purring (cats sometimes purr when in pain)

Sources and Further Reading

• AVMA: Cat Care — Feline health guidance from the AVMA
• ASPCA: Cat Care — Cat health, behavior, and wellness
• Cornell Feline Health Center — Research-based feline health information