Is It Bad For Cats To Drink Milk?

What if there’s a parallel universe where cats are our masters and keep us as pets. Wait, hang on… that’s our universe.

OK, let’s try that again. Imagine a universe where cats actually look after humans. I can just hear the sorts of things they would say:

  • You really must get one, they’re so cute.
  • Have you seen how they carry things around with their cute little hands?
  • They beg so adorably for ice cream or chocolate.
  • I train mine using those horrible smelly sweets.

Then there would be the responsible cats who say that you should never give your human any chocolate, ice cream or sweets. It’s just not good for them and shame on you other cats for spoiling your human so.

Now back to reality. Hopefully, you can see what I’m doing. A Google search will tell you that cats are lactose intolerant and that milk causes gastrointestinal upsets. All this is true, in theory. In practice, it’s all about the individual cat and the amount you give.

Why Give Cats Treats

Cats aren’t dogs. I don’t feel any need to give my dogs treats because everything they get is a treat to them. Crumbs? Awesome! You dropped a piece of banana? Double awesome! An unguarded cat litter box? I’ve died and gone to heaven!

Cats don’t work that way. Cats aren’t going to give away their appreciation for just any old thing. You’ve got to earn it.

Getting a cat to do a trick or even just to come when called feels like a major life achievement. That’s why most cat owners when asked will admit to feeding treats to their cat. Things like meat offcuts, fish, or odd personal tastes like Grendel and his seaweed rice crackers. So what about milk?

Can Cats Drink Milk?

In practice, cats love milk and I have never known a problem with an owner feeding it. Yes, I’m sure it’s possible to give them an upset tummy but we aren’t exactly running milking sheds here. It’s usually only a small amount on offer.

Of course, some cats will suffer food allergies to any ingredient. If you look at this data on cat food allergies you’ll see why I stop dairy and fish in any cat with skin or gastrointestinal problems. Then there are kittens, who should never be given milk containing lactose. However, these are the exceptions to a generally harmless treat.

Is It OK To Give Cats Milk?

As long as you only feed a treat-sized amount and your cat is healthy, you are doing no harm. Like most things, it’s better to give the same amount regularly than causing big changes in the diet each day. This allows the gut to adapt.

cat lapping milkAs for lactose, small amounts are tolerated by most cats. If you’re worried about the lactose you can buy special lactose-free pet milk, or use yoghurt which has a naturally lower lactose level.

How do I give Grendel a milky treat? Every morning I froth milk for our coffees and ‘somehow’ there’s always too much froth left over. The warm frothy kitty-cino is probably only a splash of milk but it’s one of the many highlights of his day.

What Treats Are Bad For Cats?

The good news is that cats generally are clever enough to avoid problems. This list of dangerous foods for dogs is also true for cats if they actually ever ate them. As for foods that might just be too rich or unbalanced, the solution is in the very word we use: ‘treat’. If you keep them to under 5% of a lean diet the only risk you take is that your cat may become more demanding, not any less healthy.

Related: How to keep cats from getting overweight

By Andrew Spanner BVSc(Hons) MVetStud, a vet in Adelaide, Australia. These blogs are from a series regularly posted on Facebook and Twitter. Like or follow our page or subscribe via email to read the latest.
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Help! My Dog Has Diarrhoea

At A Glance (Details Below)

Emergency Care

When To See The Vet For Diarrhoea

It’s especially important to see a vet straight away for:

  • Puppies, old dogs or those without up-to-date vaccination
  • Vomiting, not eating or other signs of illness
  • Blood in the stool, excessive diarrhoea or possible poisoning
  • Dry, tacky gums or any other sign of dehydration


Now dive deeper… Read more

The New Parvovirus Strain In Australian Dogs

UPDATE: We are glad to inform you that our standard Nobivac DHP vaccine has been proven to protect against strain CPV-2c. See more below.

Every dog owner’s worst nightmare is Parvovirus. This week the detection of a new strain in Australia was announced. Although there’s no reason to panic, here’s what vets and dog owners need to know.   Read more

Why Does My Dog Have Diarrhoea?

Diarrhoea is when dogs pass poo (faeces) that is softer than usual, more frequent or more is passed than normal. Vets call it diarrhoea any time faeces are less solid than usual, not just when they are watery.

This page covers diarrhoea in general. Please also visit our page on how we treat the most common type of diarrhoea in dogs.

What Does Colour, Mucus or Blood Mean?

  • If diarrhoea has red blood or mucus, especially if a dog is also straining, it’s probably caused by a problem in the colon, or large intestine.
  • If diarrhoea is yellow, brown or green, it probably has a small intestinal cause, especially if it’s quite runny.

Knowing which part of the intestine it comes from can help your vet decide on the right treatment. It’s always a good idea to get a dog checked by the vet. Some simple diarrhoea caused by eating something silly can go away by itself within 24 hours. However, if it hasn’t passed by then, or if your dog is unwell, please see your vet.

Be careful: many causes of canine diarrhoea can also affect human health. Read about what you can catch from dogs here.

Causes of Diarrhoea in Dogs

Acute, or short-term causes of diarrhoea in dogs include:

Eating Something Rottendog eat vomit

Dogs are masters of the ‘eat it and see if it’s OK’ philosophy. Sometimes it’s not OK. We discuss diarrhoea caused by eating the wrong thing here.

Viral Infection

In Adelaide, almost any dog who goes out not protected against parvovirus is at high risk of serious diarrhoea and death. Distemper, though now rare in urban areas, also causes diarrhoea early in its course. Read more about parvo and distemper in dogs here.
Coronavirus produces similar but milder diarrhoea and can be a problem in shelters and breeders.

Bacterial Infection

Salmonella and Campylobacter can cause diarrhoea in certain cases and are one of the reasons why we don’t recommend raw chicken be fed to dogs. Read more here on making safer raw diets for dogs.

Protozoal Infection

Giardia is an extremely common cause of diarrhoea in puppies, and will even persist into adulthood if not recognised.

Intestinal Worms

Yes, all worms regularly cause diarrhoea without regular use of dewormers, especially hookworms, roundworms and whipworms in dogs.

Haemorrhagic Gastroenteritis

HG is a true emergency caused by a sudden onset of severe watery diarrhoea with fresh blood. Dogs are usually very lethargic, sick and vomiting. They rapidly go into shock from fluid and electrolyte loss and can die within hours if not treated.

The cause is unknown but recovery is usually rapid if fluid resuscitation can be given quickly enough.

Do Antibiotics Cause Diarrhoea?

Yes, dogs can get diarrhoea from almost any antibiotic. If your dog has developed diarrhoea after starting a course of antibiotics, please contact your vet straight away. If a vet is not available, it’s probably best to stop the antibiotics unless the infection itself is life-threatening.

Does Changing The Food Cause Diarrhoea?

It’s very rare to see diarrhoea caused simply by changing brands of dog food. Dogs who get diarrhoea with diet change usually have been been fed large amounts of an unusual food. Examples could be feeding leftovers, raiding the kitchen cupboards or after eating a fatty marrowbone.

Causes Of Chronic Diarrhoea

We call diarrhoea ‘chronic’ when it goes for 3 or more weeks. Most of these dogs by now have extra symptoms including:

  • Nausea & vomiting
  • Abdominal pain
  • Not eating or a picky appetite
  • Weight loss
  • Harsh dry coat

The causes of this are usually trickier and require extra tests for diagnosis and treatment.

Pancreatic Insufficiency

Cause: a lack of digestive enzymes
Test: Trypsin Like Immunoreactivity blood test
Treatment: replacement enzymes and supplements.

Addison’s disease

Cause: a lack of steroid hormones
Test: Routine blood testing and ACTH stimulation test
Treatment: replacement hormone treatment


Cause: anything causing a partial intestinal obstruction can cause chronic diarrhoea. These can be a foreign body, a tumour or an intussusception (telescoping of the bowel).
Test: ultrasound examination, X-rays and exploratory surgery
Treatment: surgery


Many serious toxins of dogs such as snail bait cause diarrhoea but usually that’s not the main problem. Sometimes heavy metals such as Zinc and Lead can cause diarrhoea without many other signs.

Food Intolerance

Cause: immune-mediated or allergic response to food allergens.
Test: cure by elimination of the offending food item and recurrence when challenged with the item confirms the suspicion
Treatment: restricted diets. Read all about testing and treatment of food allergy and intolerance here.

Inflammatory Bowel Disease

Cause: unknown but suspected to be immune-mediated and genetic in origin. More common in the Weimaraner, Rottweiler, German Shepherd Dog, Border Collie and Boxer.
Test: Only diagnosed by first ruling out all other causes of diarrhoea, possibly including intestinal biopsies
Treatment: may need immunosuppressive drugs if no response to dietary or antibiotic trials.

Liver & Kidney Disease

Cause: Organ failure
Test: routine blood testing should be enough to find it
Treatment: ideally a liver biopsy is required to treat liver failure, although even liver failure diets alone can help. Read here about the treatment of kidney disease.