The 8 Most Common Cat Health Problems (and When to See a Vet)

Cats are masters of hiding illness — a survival instinct from their days as both predator and prey. By the time a cat shows obvious signs of feeling unwell, a problem may have been brewing for some time. Knowing what to watch for gives you the best chance of catching issues early, when they're most treatable.

1. Dental Disease

By age three, over 70% of cats show signs of periodontal disease. Tartar builds up, gums inflame, and bacteria can enter the bloodstream and damage the heart, kidneys, and liver. Signs: bad breath, pawing at the mouth, dropping food, reduced appetite. Prevention: annual dental check-ups, dental treats, and ideally tooth brushing (yes, really).

2. Kidney Disease

Chronic kidney disease (CKD) is one of the leading causes of death in older cats. The kidneys lose their ability to filter waste, and by the time blood tests confirm CKD, up to 75% of kidney function may already be lost. Signs: increased thirst and urination, weight loss, vomiting, poor coat. Annual blood tests for cats over 7 are highly recommended.

3. Urinary Tract Issues (FLUTD)

Feline Lower Urinary Tract Disease covers a range of conditions affecting the bladder and urethra — crystals, infections, blockages, and idiopathic cystitis (often stress-triggered). Male cats are at particular risk of life-threatening blockages. Signs: straining in the litter box, frequent small urinations, blood in urine, crying when urinating. A blocked male cat needs emergency veterinary care within hours.

4. Obesity

More than half of pet cats in developed countries are overweight. Obesity dramatically increases risk of diabetes, joint disease, liver problems, and respiratory issues. If you can't feel your cat's ribs without pressing firmly, they're likely overweight. Address with measured feeding, increased play, and vet guidance.

5. Diabetes Mellitus

Linked to obesity, diabetes is increasingly common in cats. The pancreas fails to produce sufficient insulin, or cells become resistant. Signs: excessive thirst and urination, weight loss despite good appetite, weakness in the hind legs. Many diabetic cats can achieve remission with diet change and, initially, insulin treatment.

6. Hyperthyroidism

The most common hormonal disease in older cats. An overactive thyroid gland accelerates metabolism. Signs: weight loss despite increased appetite, hyperactivity, vomiting, poor coat, increased thirst. Treatable with medication, radioactive iodine therapy, or surgery.

7. Respiratory Infections

Upper respiratory infections (cat flu) are common, especially in cats that go outdoors or were once strays. Usually caused by feline herpesvirus or calicivirus. Signs: sneezing, runny nose and eyes, congestion, mouth ulcers. Most cases resolve with supportive care; secondary bacterial infections may need antibiotics. Vaccination prevents the most serious forms.

8. Parasites

Fleas, ticks, roundworms, tapeworms, and ear mites are common even in cats that appear healthy. Signs vary by parasite but include scratching, coat changes, scooting, visible worms in faeces or around the tail, and dark "coffee ground" debris in the ears (ear mites). Year-round prevention with vet-recommended products is far easier than treating an established infestation.

When to Call the Vet Immediately

• Straining to urinate with nothing produced (especially males)
• Difficulty breathing or open-mouth breathing
• Collapse or sudden inability to use hind legs
• Suspected poisoning
• Seizures
• Eye injuries
• Wounds from cat fights (infection risk is high)