Why you shouldn’t give chocolate to dogs and cats

Children eat chocolate from a very young age and never have an issue with it (apart from the occasional tantrum when they are denied it), so why is chocolate toxic to dogs and cats?

The troublesome substance in chocolate is called theobromine and it comes from the cocoa beans. Cocoa beans, the seeds of the cocoa tree (Theobroma cacao) are processed into cocoa solids, used in the production of normal chocolate, and cocoa butter, which is the basis for white chocolate. Cocoa butter barely contains any theobromine, so the rest of this article will be about milk or dark chocolate and other products containing cocoa solids (cocoa powder, powdered hot chocolate, chocolate ice cream and other desserts with cocoa or chocolate in them).

Theobromine is a stimulant similar to caffeine, it affects the nervous system (making one more alert) and the cardio-respiratory system (making the heart and lungs work harder).

In moderate amounts, this gives one a boost of energy and alertness, but in high enough quantities could lead to serious consequences, overloading the heart and respiratory muscles to the point of collapse or stimulating the central nervous system until it develops seizures.

Theobromine is easily absorbed from the stomach and gut and, whilst humans have a very active enzyme that quickly renders it inactive, dogs and cats have got the ‘lazy’ version of that enzyme and it breaks down theobromine much slower. Together with their much smaller body weight (compared to a human), this means that the amount of theobromine can quickly build up to a toxic level for them.

Besides that, the sugar and fat amounts in the chocolate itself or the chocolate-containing desserts can cause temporary digestive troubles like an upset stomach, enteritis or even a bout of pancreatitis.

Symptoms of chocolate poisoning

Sometimes you will know immediately that your dog had chocolate, either because you catch them eating it or discover the empty wrapping or packaging soon after the chocolate thief has helped themselves to your treat.

But sometimes the fact that your pet had chocolate remains unknown for a while and the symptoms of chocolate poisoning may show up first. These are:

• vomiting and/or diarrhoea, sometimes with blood in it,

• a tender tummy: looking uncomfortable, not lying down, stretching repeatedly or moving oddly, whining, crying when their abdomen is touched,

• restlessness and hyperactivity,

• drooling,

• increased thirst,

• wobbliness.

In cases of severe toxicity, the signs can also include:

• an increased breathing rate,

• muscle tremors,

• urinary incontinence,

• convulsions or seizures.

The signs of chocolate toxicity are usually seen within the first 24 hours after ingestion. Sometimes their onset can vary from as early as 4 hours to as late as 72 hours after the fact.

When to see your registered vet

Is any amount of chocolate toxic to dogs and cats? Thankfully not!

The toxic effects are dose-dependent. The smaller the pet and the more cocoa solids they had, the higher the risk. Thus, the higher the proportion of cocoa in the product, the greater the risk. Pure dark chocolate, containing 60-85% cocoa, ranks at the higher end of this spectrum and is the most dangerous for pets.

Use this calculator developed by our colleagues at Vets Now to check how likely it is for the chocolate amount your dog had to be dangerous for them.

The calculator can be used for cats too. The toxic dose for them is similar, but they are less likely to eat chocolate because they cannot taste sweet very well and generally don’t care for sweet treats. (They will try to steal your bacon instead.)

Take your pet to the vet if:

• the calculator indicates the ingested amount as high risk,

• you are not sure how much chocolate they had but it’s likely to be significant,

• you see any concerning symptoms.

Treatment of chocolate poisoning

The treatment will obviously depend on the ingested quantity of cocoa solids and what kind of symptoms the animal is showing.

For most dogs, induced vomiting to empty the stomach of the remaining chocolate in it before the theobromine gets absorbed and an absorbent like activated charcoal to be given with food at home over the next 24 hours is sufficient.

Vets use a special substance that, when injected under the skin, triggers vomiting in dogs (called an emetic), please do not attempt to induce vomiting at home, especially with salty water or salt, this could easily cause a salt toxicity and make the situation much worse.

The activated charcoal for veterinary use is a black liquid or paste of a certain concentration. It is different from the charcoal tablets used in humans for gassy guts (don’t give those to your dog either). Your vet will calculate and tell you/mark on the label the right dose to give your dog.

Pets that have eaten a large amount of cocoa solids a while ago (meaning there was plenty of time for the stimulant to get absorbed to the bloodstream) and/or showing symptoms like increased excitability, breathing and heart rate might need to be admitted for monitoring.

Their treatment also starts with making them vomit and administering activated charcoal, but may also include placing them on an intravenous drip and medication to control their heart rate, blood pressure and prevent seizures.

Luckily such cases are rare and most dogs get away with having to bring up their stomach content and eat black food for a day.

What can you do

The obvious advice is not to feed your dog chocolate or chocolate-containing treats or leave these somewhere where they can help themselves to them. Be particularly vigilant with children in the house, especially around holidays like Easter and Christmas when there’s plenty of chocolate around.

If you are baking, make sure that the cocoa is kept out of the dog’s reach. Do not leave the finished baked product to cool within the reach of naughty paws either!

Use cocoa shell mulches in your garden with care, avoid them if you have one of those dogs that tries to nibble and/or eat everything they see.

Use the calculator to check the risk of chocolate ingestion whenever you have a suspicion your dog may have had some. If you do not know how much your dog weighs, weigh yourself on a bathroom scale with and without the dog to find out.

Register with FirstVet and give us a call if you’re not sure how to use the above mentioned calculator or how much chocolate is in the product that the dog ate. We’d be happy to help you with advice! Keep for us as much of the wrapper as possible, knowing the exact type of product is very helpful.