Signs of poisoning in dogs

Unfortunately, our hungry dogs don’t usually distinguish between what’s good for them to eat, and what could be potentially dangerous.

Many items inside and outside the home can be harmful to dogs if ingested – from household chemicals, medicines and certain plants, to foods your dog definitely shouldn’t eat.

Sometimes it may be evident – from a half-chewed packet, missing food or a mangled plant – what your dog has been sneakily eating. But on other occasions, the only clue that they’ve ingested something they shouldn’t are the physical after-effects.

Dog poisoning symptoms are often non-specific and can range from subtle to severe. Although these symptoms are more commonly caused by non-toxic causes, you might see any of the following:

• Vomiting or dry heaving
• Diarrhoea
• Uncontrolled drooling
• Blood in their urine or poo
• Loss of appetite
• Agitation or lethargy
• Unsteadiness on feet
• Breathing difficulties
• Seizures or tremors
• Increased heart rate or temperature
• Drinking or peeing more than usual
• Internal bleeding (indicated by pale gums, coughing up blood, weakness or collapsing)

Obviously, not every dog with lethargy, vomiting or diarrhoea has been poisoned – the symptoms above can be associated with a range of ailments. But you know your dog best, so if you’re worried, or if they’re experiencing acute or alarming symptoms, you should always seek advice from your vet straight away.

If you’ve got an inkling of what your dog has been eating from the leftovers, then always make a note of the item, take a photo or take it with you to the vet. Don’t try to make your dog sick yourself, unless your vet advises you to do so.

Below, we look in more detail at the dog poisoning symptoms associated with common home-and-garden toxins.

Chocolate, especially dark chocolate and cocoa, contains a stimulant called theobromine that can cause serious health problems in your dog. If your dog ate chocolate, you might notice any of the following:

• Diarrhoea
• Vomiting
• Hyperactivity
• High blood pressure (which may cause disorientation, seizures, weakness or nosebleeds)
• High temperature
• Painful abdomen
• Raised heart rate
• Dehydration or drinking and peeing more than usual

If your dog has eaten chocolate or you suspect they have, take them to your vet as soon as possible – ideally within two hours. If you’re able, take the packaging from the chocolate and try to work out exactly what, and how much, they’ve eaten. This will help your vet decide the best treatment.

The vet is likely to make your dog vomit to bring up what they’ve eaten. They may also prescribe activated charcoal, which binds to theobromine to prevent it being absorbed. If your dog has eaten a lot of chocolate or they ingested it a while ago, they may need additional treatment, such as fluids and blood tests.

Members of the onion (allium) family contain a compound called n-propyl disulphide, which can break down your dog’s red blood cells and lead to potentially life-threatening anaemia. If your dog has eaten onions, shallots, garlic, leeks, chives or foods made with onion or garlic powder, this can lead to a range of short- and long-term dog poisoning symptoms:

• Diarrhoea
• Vomiting
• Decreased appetite
• Oral irritation
• Rapid breathing/panting
• Increased heart rate
• Pale gums
• Jaundice
• Weakness or lethargy
• Fainting
• Darker/reddish-coloured urine

Some slug and snail pellets contain a poison called metaldehyde, which unfortunately is one of the most common causes of fatal poisoning in dogs. Signs of metaldehyde poisoning include:

• Vomiting
• Drooling
• Panting/breathing difficulties
• Unsteadiness on feet
• High temperature
• Twitching or tremors
• Seizures or convulsions
• Respiratory failure/collapse

While slugs and snails aren’t inherently toxic to dogs, eating one isn’t good news. These creatures (and their slime trails) can carry a potentially deadly parasite called lungworm, infecting your dog if ingested. Infected dogs can gradually develop a range of symptoms over time, including:

• Coughing
• Weight loss
• Vomiting
• Diarrhoea
• Lethargy
• Internal haemorrhaging (bleeding)
• Rapid breathing/breathing difficulties
• Seizures
• Collapse and shock
• Blindness

Rodent poisons often contain warfarin, a chemical that prevents blood clotting. In large amounts, it can lead to excessive, potentially fatal bleeding. If your dog has inadvertently eaten one of these rodent poisons, symptoms may take a few days to manifest, as the bleeding may be occurring internally. Look out for:

• Coughing
• Lethargy
• Unexplained/excessive bruising
• Bleeding from the mouth, gums or nose
• Blood in their urine or poo

Other everyday household items that can cause signs of poisoning in dogs include the sweetener xylitol; supplements containing vitamin D, iron or calcium; painkillers such as ibuprofen, and other human medicines.

If you’re worried your dog has eaten something they shouldn’t, never wait to see whether they get worse – immediate treatment could make all the difference. And as we’ve seen, treating cases of poisoning in dogs can be complicated and costly, so don’t overlook the importance of dog insurance.