Constipation in your cat
Constipation in cats is to me a very real and worrying condition. I lost my very first patient under anaesthetic when my husband and I first graduated as vets so I always take constipation very seriously.
wI only remember her as an old brown tabby in severe discomfort as her abdomen contained a hard lump of faeces. Even an owner would have felt it as it was so large but she only witnessed her sad old pet unable to pass anything at all and straining continuously.
wWith the enthusiasm of a new graduate and anaesthetics of 13 years ago (anaesthetics in pets are now comparable to those in humans), I remember having her under anaesthesia and looking forward to removing the bulk of her faeces manually with my gloved index finger up her bottom, a large spout filled with lubrication and a tube also in her bottom and my other hand gently pushing the large mass towards her rectum; when she stopped breathing and died so quickly.
w I was devastated as the little old cat had died because of being constipated and my negligence at forgetting how serious it was and forgetting to give her fluids intravenously. I have never forgotten since and it has taught me to teach everyone else that a constipated cat is usually very dehydrated and should be taken very seriously.
wConstipation occurs when your cat shows signs of pain and crying when trying to pass faeces.
wIt is very common and easy to see in your pet. Be careful to distinguish it from a problem with urinating. Your cat's posture is quite different with this and cats tend to be more lethargic when constipated.
wThere may be repeated bouts of constipation in your cat where the large intestine can become swollen and loses its ability to push faeces out in a condition called megacolon, literally meaning large colon. This can be very serious in your cat and requires surgery.
Causes of Constipation
wYour cat is reluctant to pass faeces because of behavioural reasons or medical reasons.
wBehavioural reasons may include reluctance to use a dirty litter tray, competition for litter trays, dislike of the litter tray substrate used and association with an unpleasant experience whilst passing faeces or even a litter tray in an inappropriate area such as a very busy section of the house.
wPain in the lower back, tail head, hips or knees may make squatting and straining uncomfortable. There could be a number of reasons for this pain, but one is abscesses in the lower back from a bite wound when your poor cat has been running away from an aggressor.
wForeign bodies inside the colon or anal area will also result in painful defaecation, as will anal sac infections.
wUrinary tract problems may also make defaecation painful.
wDehydration can be the cause of constipation as the colon is the main area in the digestive tract where water is reabsorbed. Cats with kidney failure usually suffer with dehydration and can become constipated.
wThe nerves that control the contraction of the bowel may be damaged as a result of trauma, such as road traffic accidents if your cat's tail is caught under the wheel or tail-pull injuries.
wPelvic canal deformities can cause narrowing of the pelvic canal and compression of the colon where it passes through the pelvic canal. Although birth defects can result in narrowing, the most common cause of narrowing is a healed pelvis from an old pelvic fracture as occurs in road traffic accident victims. Faeces build up behind the area of constriction and a megacolon can develop with time.
wAs well as narrowing from external pressure, an area of the colon itself may become narrowed. This is called a stricture, and may be associated with scar tissue in the bowel wall from old injuries. Tumours may also cause an obstruction within the colon, as can foreign bodies, preventing passage of faeces past them.
Idiopathic megacolon
wThis is where none of the above factors are the cause of the constipation and there is no known cause. It is thought to be due to a problems with the nerve transmission from the nerves to the smooth muscle, so is very hard to treat.
Diagnosing Constipation
wIn addition to the history and performing a physical examination, your vet may need to perform further tests.
wBlood tests are useful to check for underlying organ problems such as kidney disease, or calcium or potassium abnormalities that can lead to muscle weakness.
wX-rays can help with identifying back, hip and pelvic problems, and we can show you how severe the constipation is.
wFurther tests involve an enema of barium which is introduced into the colon and may show up abnormalities in the wall of the colon.
wA colonoscopy shows the same but not every surgery will have an endoscope, and some vets will take a biopsy of the colon to send to the laboratory to look for abnormal cells in the wall lining.
Treating constipation in your cat at home
For practical advice on treating constipation in your cat and other common problems that do not always need a trip to your vet, click on my e-book below.
Return to cat health
