1. Difficulty breathing

This is the most urgent emergency any individual — cat, dog or human — can face. Death occurs after three minutes without breathing, so cats with breathing difficulties are on the edge of disaster. Breathing problems in cats can be hard to recognize at first. Symptoms to watch out for are heaving sides, breathing with the mouth open, coughing, wheezing, abnormal respiratory noises, and the catch-all appearance of “breathing funny.”
2. Abnormal urination in male cats

Yes, urinary obstruction is a cat emergency.
This has the potential to be a symptom of one of the most serious crises any cat can face: urinary obstruction. This condition, which is fatal if not treated, occurs when cats are unable to urinate. For anatomical reasons, it occurs almost exclusively in males. Cats with the condition suffer agonizing pain, and then rapid progression to kidney failure, potentially bladder rupture, and high blood-potassium levels that cause cardiac arrest. Initial symptoms may be subtle: Affected cats may urinate outside the litter box, strain but produce only small quantities of urine, vocalize, or groom their genitals excessively. Therefore, any male cat with any urinary irregularity whatsoever should be checked by a vet immediately. Be aware that female cats with urinary irregularities also should see the vet. They are not likely to die from the problem, but they are likely to be suffering from discomfort that warrants treatment.
3. Signs of severe pain or obvious distress

Bring your kitty to an emergency vet immediately if you notice this one. Pain itself always warrants treatment, but it also can be a sign of more serious problems such as urinary obstruction (see above) or aortic thromboembolism (see below). Symptoms of pain and distress include vocalizing (howling), panting, hiding and overreacting to contact with a painful area.
4. Sudden paralysis of the hind end

Get your cat to the vet ASAP if you notice signs of paralysis of the hind end.
While we’re on the subject of pain, we should discuss an emergency that is among the most painful events that can happen to a cat: aortic thromboembolism, or ATE. ATE is a complication of heart disease in cats in which a blood clot lodges in the rear (usually) legs. It causes sudden paralysis of the hind end. Affected cats usually will pant, vocalize and show other signs of distress. It requires immediate veterinary attention.
5. Stopping eating and/or drinking

This often means serious trouble. It is not normal for any individual to go a full day without eating when food is available, and not eating can be a symptom of (kidney failure, complications of diabetes, intestinal obstruction) and a cause of (fatty liver) major health problems.
6. Protracted vomiting and/or diarrhea

Vomiting and diarrhea can be a cat emergency!
This requires immediate veterinary attention, especially when blood is present. Almost all cats occasionally yak or have soft stools, and such incidents usually aren’t emergencies. But cats who vomit repeatedly or have blowout diarrhea should see the vet immediately.
7. Known ingestion of toxins

Ingestion of toxics such as lily or antifreeze should be treated immediately. Rapid action can dramatically improve outcomes in many different types of toxicities.
8. Profound lethargy or collapse

This should trigger an urgent trip to the vet. Profound lethargy often manifests as “not moving,” hiding in one room for a protracted period, and not reacting to stimuli (such as the can opener or the dog) in a normal fashion.
9. Seizure

Although a solitary seizure is not likely to be life threatening, owners should be aware that seizures often come in clusters that get worse over the course of several hours. They also can be a symptom of exposure to toxins such as mold or low-quality flea control products. Cats who suffer a seizure should go straight to the vet.
10. Major trauma

This should always trigger a veterinary visit. Owners of cats with gaping wounds or massive hemorrhage usually know this intuitively. However, sometimes cats who have fallen from height, been hit by cars, struck by garage doors or attacked by large dogs can have major internal injuries yet appear unharmed after the incident. Any time you are aware of such an occurrence, your cat should be checked out.
11. Fights with other cats

Cats who have been in fights with other cats should see the vet sooner rather than later. Cat fight wounds are relatively easy to treat with antibiotics if they are caught early. If a delay occurs, an abscess may develop that requires anesthesia and surgery.
Cat owners should remember that the above list is not exhaustive; it is not possible to list (or even imagine) every type of emergency situation that a cat might face. I wish to reiterate that if you are in doubt, you should call a vet, or simply go to the vet.

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