Abdominal Swelling in Cats: Causes, Signs and Treatment

If you’ve noticed your cat’s abdomen is looking larger or more rounded, this is worth paying attention to. Sometimes, it will just be the case of a cat who has put on a few pounds after over-indulging. Other times, it will be an indication of something more serious.

It can be very difficult to determine what is causing abdominal swelling without consulting with a veterinarian. For this reason, any new swelling is a reason to have your cat checked over. Read on to learn all you need to know about feline abdominal swelling.

What Causes Abdominal Swelling in Cats?

There are lots of things that can lead to a swollen abdomen in your cat.

Fluid Accumulation and Ascites

A lot of the time, the swelling is a result of ascites. This is a build up of fluid within the abdomen which pushes on the organs and abdominal muscles, leading to a visible swelling.

Feline Infectious Peritonitis (FIP)

A viral infection called Feline Coronavirus is prevalent in the UK and about 5% of FCoV infected cats will go on to develop FIP. While FIP used to be seen as a death sentence, emerging therapy has shown huge success in recent years.

Heart, Liver or Kidney Disease

When the heart cannot pump efficiently, the liver fails to make enough protein, or the kidneys cannot filter waste, the result can be ascites.

Cats with organ disease often have other signs, such as lethargy, excess thirst and muscle wastage.

Toileting Trouble

Be mindful that a ‘blocked bladder’ can be a cause of abdominal swelling, particularly in young adult males. They will be distressed, and will constantly try to urinate but cannot.

Severe constipation could also potentially lead to a swollen abdomen, particularly when there is a lot of gas build up.

Internal Masses or Tumours

Anything that physically occupies space in the abdomen can cause it to protrude. This can occur, for example, when an organ is enlarged or when there is a cancerous growth.

Internal Bleeding or Peritonitis

Blood or inflammatory fluid within the abdominal cavity will, when enough is present, cause it to become visibly distended. If it is blood, the cat may be pale and weak, due to the anaemia.

Benign Causes

Sometimes, swelling is due to something like fat build up or pregnancy. Of course, if it is fat accumulation, the cat should be otherwise healthy and this would be a gradual change.

With pregnancy, this is going to be an un-spayed cat who has recently spent time with an un-neutered male.

Kittens With a Swollen Belly

Be aware, that a kitten who is acting normally but who has a swollen tummy may simply have gas build up after eating too quickly or swelling caused by internal parasites. These kitties are usually happy and playful, but should still be seen for a routine check up.

What Are the Signs of Abdominal Swelling in Cats?

It is not always easy to spot abdominal swelling, particularly in very furry cats.

A Visibly Enlarged or Rounded Belly

Rather than being concave, the abdomen will protrude out. Typically, the belly will feel ‘doughy’ and quite firm.

Weight Loss Alongside a Distended Abdomen

Some owners mistake abdominal swelling for fat gain. However, these cats have generally lost fat. This can be seen as a ‘skinny body’, or a skeleton that is easier to feel over the rib, pelvic and spinal areas.

Lethargy, Vomiting or Loss of Appetite

For many cats, they have additional symptoms such as vomiting or lethargy. This will be due to the underlying disease processes.

Having fluid on the abdomen means less space for the stomach and intestines, so appetite is usually negatively affected too.

Breathing Difficulties or Rapid Breathing

It is common for abdominal swelling to present alongside trouble breathing. This can be because there is less space for the lungs to expand. It can also be due to the primary cause e.g. heart disease or internal bleeding.

Is Abdominal Swelling in Cats an Emergency?

Certainly, for many cats, these symptoms will be an emergency.

Sudden or Rapidly Worsening Distension

It is a red flag if your cat’s abdomen suddenly enlarges. Similarly, if it has been a little swollen but is suddenly much larger, this must be taken seriously.

Difficulty Breathing or Pale Gums

Changes in circulation can lead to pale gums, weak pulses or trouble breathing. This can be life-threatening and requires immediate action.

Collapse, Weakness or Severe Pain

At the point where your cat is weak, dizzy or collapsing, they need veterinary support. Similarly, if they are showingsigns that they are in pain, we want to intervene.

What Should You Do if Your Cat's Abdomen is Swollen?

If you suspect your cat does have abdominal swelling, you’ll want to act straight away.

Keeping Your Cat Calm and Still

As your cat may be in shock, or dealing with a low circulating blood volume, try to reduce their stress levels. This includes keeping their surroundings calm and quiet, and minimising any handling.

What Not to Do Before Seeing a Vet

It is best not to apply pressure or to try and massage the abdomen, as this could do more harm than good and may cause discomfort.

Do not be tempted to trial any over the counter medication. Many medications designed for humans are highly toxic to cats.

When to Contact an Emergency Vet

Red flag signs that would demand emergency vet care would include:

• Sudden or obvious abdominal swelling

• Pale gums

• Weakness or lethargy

• Trouble breathing

• Recent trauma

• Difficulty passing urine or stool

How Do Vets Diagnose Abdominal Swelling in Cats?

Your vet will be experienced when it comes to feline abdominal swelling as it is a common problem.

Physical Examination and Abdominal Palpation

They will examine your cat, palpating the abdomen to check for any organ enlargement, tumours or fluid build up. They will also be assessing your cat’s general health, including their circulatory system and temperature.

X-Rays and Ultrasound Imaging

Imaging is a great way to visualise the contents of the abdomen and to check for the presence of free fluid.

Blood Tests and Fluid Analysis

Blood tests will be run to check organ health and to assess protein levels, as well as to check for any evidence of infection or inflammation.

Free fluid within the abdomen may be sampled, which can be diagnostic in cases including FIP or sepsis.

How is Abdominal Swelling in Cats Treated?

Treatment will ultimately depend on the diagnosis.

Draining Excess Fluid From the Abdomen

While it may seem like an obvious step, it is not common to drain fluid. This is because it usually just re-fills. However, it may be drained to make the pet more comfortable in some cases, if there is a very large amount.

Medication for Underlying Conditions

Medicine may include diuretics (water tablets) for those with heart disease or wormers for kittens with heavy parasite burdens.

Surgery for Tumours or Organ Disease

Sometimes, surgery is recommended. This would be the case, for example, if there is a tumour of the spleen, an intestinal obstruction, or a liver shunt.

Supportive Care and Hospitalisation

Most cats will require supportive care in the form of intravenous fluids, assisted feeding and cage rest.

Can Cats Recover From Abdominal Swelling?

While many cats can recover, very sadly, some conditions carry a grave prognosis.

Factors That Influence Recovery

The main factor is the underlying cause of the swelling. Something like worms in a kitten has an excellent prognosis. However, a cat with advanced cancer or underlying disease such as hyperthyroidism or heart failure is less likely to recover.

Your cat has a higher chance of recovery if they are young and if their symptoms are minimal. How quickly the cat receives care and their response to therapy will also strongly predict their outcome.

Long-Term Management and Monitoring

Going forward, your vet may wish to see your cat regularly for check ups. This is to assess for any further swelling and to manage any medication that they are on.

How Can You Help Prevent Abdominal Swelling in Cats?

Prevention of abdominal swelling is not always something that can be achieved. Still, some things that you do can make a difference.

Regular Vet Check-Ups and Health Screening

Adult cats should be seen at least once a year, while most vets recommend seeing seniors every six months or so. This way, medical issues can be detected early.

Vaccination and Parasite Prevention

Vaccines are an important part of feline health care, although there is no licenced FIP vaccine currently in the UK.

Parasite prevention is important at every age, but especially in young cats and kittens, who are the highest risk group.

Get Emergency Vet Care for Your Cat

Please contact us any time, if you suspect your cat has developed abdominal distension. Our team can advise on whether you need to be seen urgently and can book you into your nearest clinic.

Abdominal swelling in cats FAQs

How do I know if my cat's abdomen is swollen?

A swollen abdomen looks bloated and round. You might notice that your cat seems skinny everywhere except their large tummy.

Is abdominal swelling in cats always an emergency?

Not necessarily, but it often is. An old cat who is unwell and develops a sudden abdominal swelling requires urgent care. Conversely, a young kitten who has just gobbled their food, may simply have some gas build up.

Can abdominal swelling in cats be treated at home?

No, it is not recommended to try and treat your pet from home. A vet visit is essential to determine the cause of swelling, so the correct therapy plan can begin.