How to Tell When Your Cat Is Sick: A Vet’s 2025 Guide to Spotting Warning Signs & Getting Help 🐱🩺

By Dr Duncan Houston BVSc, Ask A Vet Blog

Our feline friends are masters at hiding discomfort—but early detection of illness can mean faster treatment and better outcomes. In 2025, veterinarians highlight 15 clear “red flags” that your cat may be ill. This guide explains each sign, why they matter, and when to seek professional help. Learn to be your cat’s advocate. 😊

1. 🍽️ Change in Appetite

Sudden reluctance to eat or overeating may signal health issues: dental disease, gastrointestinal upset, hyperthyroidism, or diabetes.

• What to watch: Not eating for 24–48 hours—especially in older cats.
• What to do: Offer tempting wet food; contact your vet if appetite doesn’t return.

2. 💧 Increased Thirst or Urination

Frequent drinking or litter-box use could indicate kidney disease, diabetes, or urinary tract infection.

• Note changes in water bowl levels or litter box pattern.
• If persists >24 hours, schedule bloodwork and urine tests.

3. 🚽 Litter-Box Behavior Changes

Straining, frequent attempts, diarrhea, or accidents outside the box can mean urinary issues, constipation, or GI conditions.

• Straining needs immediate vet evaluation.
• Diarrhea >48 hours—check for inflammation or infection.

4. 🤢 Vomiting

Occasional hairballs are normal, but repeated vomiting (more than once per week) is a warning sign.

• Report frequency, content, and accompanying symptoms.
• Mobility, appetite, or hydration concerns warrant prompt vet attention.

5. 😿 Weight Loss or Gain

Unexplained weight changes can be subtle—use a home body-condition guide.

• Chronic weight loss suggests hyperthyroidism, cancer, or GI disease.
• Excess weight gain risks include diabetes or arthritis.

6. 💤 Lethargy or Behavioral Shifts

If your cat becomes withdrawn, hides often, sleeps more than usual, or seems depressed, it could be underlying illness or pain.

• Even minor pain (e.g., arthritis, dental issues) can change behavior.
• A vet exam is advised without delay.

7. 😿 Respiratory Signs

Coughing, sneezing, wheezing, or nasal/ocular discharge may stem from infections, asthma, or allergies.

• Persistent symptoms warrant a vet visit—especially if breathing sounds noisy.

8. 👁️ Eye or Nose Discharge

Yellow/green discharge, squinting, or persistent tearing indicates infection, injury, or other conditions.

• Early care can prevent long-term eye damage.

9. 😖 Persistent Scratching or Hair Loss

Itching, licking, bald patches can reveal allergies, mites, or fungal infections.

• Avoid self-treating with over-the-counter meds—see your vet for proper diagnosis.

10. 🛸 Bad Oral Odor / Dental Signs

Halitosis, red gums, drooling, or difficulty eating points to dental disease or oral infections.

• Dental cleaning or treatment can alleviate pain and prevent systemic illness.

11. 🩸 Blood in Stool or Vomit

Any sign of blood needs urgent evaluation—it may be due to GI ulcers, parasites, or bleeding disorders.

• Dark, tarry stool = upper GI bleeding; bright red blood = lower GI tract.

12. 👟 Lameness or Mobility Changes

Difficulty jumping, stiffness, or limping could indicate arthritis, injury, or neurological concerns.

• Even middle-aged cats with decreased activity benefit from a vet assessment.

13. ⚠️ Fever or Heat

An ear-tip temperature >102.5 °F (39.2 °C) suggests infection or inflammation.

• Check with a feline thermometer; contact your vet about warm, painful flanks.

14. 🧭 Change in Vocalization

Unusual meowing, howling, or yowling can signal pain, disorientation (e.g. hyperthyroidism/dementia), or stress.

• Describe frequency, pitch, and timing to your vet.

15. 🌸 Coat or Skin Changes

Dull, brittle coats, excessive oiliness, dandruff, or flaky skin often indicate nutritional deficiencies, hormone issues, or allergies.

• Combine with other red flags to guide diagnostics.

🧭 Monitoring & Early Detection

• Weigh your cat monthly or use a body condition chart.
• Observe water dish and litter box daily for unusual patterns.
• Play & cuddle time: gives insight into appetite, mobility, mood.

🩺 When to See the Vet Immediately

• Refusal to eat/drink ≥24 hours
• Difficulty breathing, persistent vomiting/diarrhea, blood in waste
• Sudden weight change, disorientation, collapse

✅ 2025 Cat Health Check Checklist

• ✔ Appetite & water: normal vs. changed
• ✔ Litter habits: urination & defecation frequency
• ✔ Behavior: energy, mood, social interaction
• ✔ Physical exam: eyes, ears, coat, weight, teeth
• ✔ Mobility: jumping, walking, general movement
• ✔ Temperature: if suspected elevated

🛠️ Ask A Vet, Woopf & Purrz Support

• Ask A Vet App: Send videos or photos of concerning signs—get real-time guidance on what to monitor or when veterinary care is needed.
• Woopf: Offers tracking journals, digital body-condition guides, and mobile-friendly wellness logs to organize your pet’s health data.
• Purrz: Provides stress-reducing pheromone diffusers to support at-home comfort during illness or vet visits.

❤️ Final Thoughts from Dr Houston

Noticing the subtle shifts in your cat’s eating, bathroom habits, coat, or behavior—and acting on them—can be lifesaving. In 2025, early detection supported by careful monitoring and professional advice leads to the best outcomes. Your bond and vigilance are powerful tools in maintaining your cat’s health. If you ever suspect sickness, never hesitate to reach out through the Ask A Vet app, and consider Woopf’s and Purrz’s tools to streamline wellness tracking and home comfort. Wishing you and your feline friend a long, healthy life together! 🐾😊