Cats are very good at hiding illness, so any clear change from your cat’s normal behavior, appetite, or bathroom habits can be a sign something is wrong. If you see multiple changes at once, or any “emergency” signs, contact a vet as soon as you can.

Common warning signs

Watch for these changes, especially if they last more than a day or two or appear suddenly:

• Eating or drinking much more or less than usual, or sudden weight loss or gain

• Vomiting, diarrhea, constipation, or straining in the litter box, especially if there is blood or signs of pain

• Lethargy, hiding more, not wanting to play, or a big change in mood or personality

• Breathing changes: rapid, noisy, open‑mouth breathing, or coughing/wheezing

• Changes in grooming: very messy coat, or excessive licking/over‑grooming, hair loss, or skin irritation

• Eye or nose discharge, sneezing, or bad breath

• Limping, visible wounds or swelling, or sudden difficulty jumping or moving around

Emergency signs – go to a vet now

Get urgent vet care (emergency clinic if needed) if you notice:

• Trouble breathing, open‑mouth breathing at rest, or blue/very pale gums

• Collapse, seizures, severe weakness, or your cat being unresponsive

• Continuous vomiting, vomiting blood, or cannot keep water down

• Straining to urinate, crying in the litter box, no urine produced, or blood in urine (especially male cats)

• Major trauma (fall, hit by car, bite wounds) or heavy/ongoing bleeding

Simple at‑home checks

You can do a quick check while staying gentle and calm:

• Look at eyes, nose, and mouth: clear eyes, no thick discharge, and gums that are pink (not white/blue) are usually good signs

• Feel the body: note any new lumps, swelling, very painful spots, or sudden weight loss when you pet them

• Watch the litter box: changes in frequency, consistency, or location (peeing/pooping outside the box) can indicate illness or stress

When to call the vet

• One mild change (a bit quieter, one soft stool) that resolves in a day can be monitored closely.
• If a mild sign lasts more than 24–48 hours, or you see more than one sign at the same time, call your vet for advice or an appointment.

• Trust your gut: if your cat “just isn’t right,” it is safer to have a vet check, even if the signs are subtle.

If you describe what you’re seeing (how long it’s been going on, eating, drinking, peeing, pooping, behavior), more specific guidance can be offered, but any worrying signs above should be seen by a vet.