Why is my dog vomiting? Dr Gilson explains when to worry and when to see a vet

As a veterinarian, vomiting is one of the most common reasons I see dogs brought into the clinic. Sometimes it’s something relatively minor that resolves on its own. But at other times, it can be the first sign of a serious medical condition that requires urgent treatment.

One of the challenges in diagnosing vomiting is that it can have many different causes. I’ve treated dogs that vomited after scavenging food from a rubbish bin, puppies that have a half-chewed sock or other foreign object stuck down their throat, and older dogs whose vomiting was linked to underlying diseases affecting their organs.

The important thing to remember is that not all vomiting is an emergency. But it is essential to know when it may indicate something more serious.

Common reasons dogs vomit

Dogs are naturally curious and may be sick after eating something they shouldn’t. Some dogs deliberately make themselves vomit by swallowing grass when they feel nauseous. The grass tickles their throat, triggering the retch reflex.

Some of the more common causes of vomiting include:

• Eating spoiled food or scavenging in the rubbish
• Sudden changes in diet
• Eating too quickly, or too much
• Food allergies or sensitivities
• Intestinal parasites
• Viral or bacterial infections
• Swallowing foreign objects such as toys, socks, bones, or plastic
• Exposure to toxins
• Pancreatitis
• Kidney or liver disease
• Certain cancers, particularly in older dogs

In many cases, a single episode of vomiting may not be cause for concern, especially if your dog otherwise appears bright, alert, and active.

When you can monitor your dog at home

If your dog vomits once and then returns to normal behaviour, eating, drinking, and interacting as usual, careful monitoring may be all that’s needed.

Keep an eye on their:

• energy levels
• appetite
• water intake
• any further vomiting
• stool consistency

Ensure fresh water is always available and avoid offering rich treats or table scraps.

However, if vomiting continues or your dog’s demeanour changes, it’s time to seek veterinary advice.

Signs that should never be ignored

There are certain situations where I recommend contacting your veterinarian immediately.

Please seek veterinary attention if your dog:

• Vomits repeatedly within a short period
• Cannot keep water down
• Appears lethargic or weak
• Has diarrhoea alongside vomiting
• Has blood in the vomit and diarrhoea
• Has a swollen or painful abdomen
• Is struggling to breathe
• Has eaten something toxic
• May have swallowed a foreign object
• Is a puppy, senior dog, or has an existing medical condition

Repeated vomiting can quickly lead to dehydration, especially in young puppies and elderly dogs.

What if my dog is vomiting yellow foam?

This is a question I hear frequently.

Yellow foam or liquid is usually bile, a digestive fluid produced by the liver. Sometimes dogs vomit bile when their stomach has been empty for a long period, particularly first thing in the morning.

Occasional bile vomiting may not be serious, but if it happens regularly or is accompanied by other symptoms, it should be investigated.

When vomiting becomes an emergency

One condition that worries veterinarians is gastric dilatation-volvulus (GDV), commonly known as bloat. Dogs with bloat may:

• attempt to vomit but produce little or nothing
• have a swollen abdomen
• pace or appear restless
• salivate excessively
• show signs of distress

This is a life-threatening emergency that requires immediate veterinary treatment.

Similarly, dogs that have swallowed foreign objects may develop an intestinal blockage, which often causes persistent vomiting and severe discomfort.

The sooner these conditions are diagnosed, the better the outcome.

What to expect at the veterinary clinic

When a vomiting dog arrives at our primary healthcare clinic, the first thing we do is try to determine the underlying cause. This may involve:

• a physical examination
• blood tests
• faecal testing

A private veterinary clinic may also carry out X-rays and an ultrasound examination.

Treatment depends on the diagnosis and may include anti-nausea medication, fluid therapy, dietary management, parasite treatment, or surgery in more serious cases.

How to prevent vomiting

While not every case can be prevented, there are a few simple steps that can reduce the risk:

• Keep rubbish bins securely closed
• Avoid feeding table scraps
• Introduce new foods gradually
• Keep toxic substances out of reach
• Supervise dogs that chew or swallow non-food items
• Ensure routine deworming is up to date
• Schedule regular veterinary check-ups

Prevention is often far easier and less costly than treating an advanced illness.

Final thoughts

Vomiting is one of those symptoms that can range from mild to life-threatening. While a single episode may not always be cause for concern, repeated vomiting or any signs that your dog is unwell should not be ignored.

As veterinarians, we’d always rather assess a dog early than see them once they’ve become seriously dehydrated or critically ill.

If you’re unsure whether your dog’s vomiting is serious, contact your veterinarian for advice. Trust your instincts – you know your pet better than anyone, and acting quickly can make all the difference.

Dr Gilson Muchopa has been in practise for 22 years – the past 12 of which he has served as Controlling Veterinarian at the Durban & Coast SPCA.

Watch this space for more tips from Dr G. If you have specific questions for our vet, please email marketing@spcadbn.org.za