My Dog Ate M&Ms [What Should I Do?]

Zack Keithy, our author, is a certified veterinarian technician (UC Blue Ash) for over 6 years (contact him here). The articles written here are based on his expertise and experience, combined with a review by our expert vet reviewers including Dr M. Tarantino. Learn more about us here.

Our canine companions bring so much joy into our lives, but having a pet also comes with some pretty heavy responsibilities.

Dogs, by their very nature, are curious. And that keen sense of smell that they have often led them into a fair amount of trouble.

Curiosity may have killed the proverbial cat, but it’s brought dogs perilously close too.

A main concern with dogs is what they manage to ingest that they shouldn’t.

A prime example, and our focus in this article, is chocolate – in particular, M&Ms.

We’ll be looking at the potential danger, signs that your dog has chocolate poisoning, and what you should do if your dog ate M&Ms.

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What Happens if a Dog Eats M&Ms?

What Happens if a Dog Eats M&Ms

If your dog has managed to devour your stash of M&Ms, it wouldn’t be the first.

Dogs are always nibbling on things that aren’t good for them.

M&Ms are problematic for dogs because of their chocolate content, and while chocolate ingestion is rarely fatal, it can cause significant illness in dogs.

We go a bit deeper about the effects M&Ms might have on your dog in the following sections.

What makes chocolate toxic to dogs?

Chocolate contains theobromine (also known as xantheose), a compound that is toxic to dogs.

When a dog consumes it, it can cause various health problems.

This is largely because a dog’s metabolism takes longer to process theobromine than a human’s. 

This bitter-tasting alkaloid is similar to caffeine and causes a number of effects in your dog’s body, including acting as a diuretic, stimulating the heart, dilating blood vessels, and relaxing the smooth muscles.

Dark chocolate and unsweetened baking chocolate tend to contain higher levels of theobromine than milk chocolate.

M&Ms typically contain milk chocolate, so they aren’t the worst for your dog, but if your dog eats enough of them, they can still pose a risk.

What are the symptoms of chocolate poisoning in dogs? 

Theobromine poisoning can affect a dog’s central nervous system, cardiovascular system, and gastrointestinal tract.

If your dog has consumed some, you may spot symptoms like:

  • Restlessness
  • Panting
  • Vomiting
  • Diarrhea
  • Muscle tremors
  • Seizures

In severe cases, coma and even death can result.

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How Much Chocolate is Toxic to Dogs?

The amount of chocolate that is toxic to dogs will depend on the size of the dog and the quantity consumed.

Generally speaking, dogs will show signs of poisoning after consuming around 20mg of theobromine per kilogram they weigh.

The symptoms are severe after consuming 40 to 50mg per kilo of body weight.

If you know what your dog weighs and roughly how much chocolate they’ve consumed, this dog chocolate toxicity meter can be really helpful.

Doggy says, you might be keen to read this too: My dog ate an Uncrustable!

What Other Foods Are High in Theobromine? 

Theobromine is largely found in chocolate and cocoa-containing products and beverages.

Cocoa powder, baking chocolate, chocolate-flavored puddings and desserts, chocolate syrups, and candies are all very high in theobromine and should be stored carefully around dogs.

Doggy says, you might want to read this too: Can dogs eat flan?

How Many M&M’s Can Kill a Dog?

How Many M&M's Can Kill a Dog

One or two M&Ms are unlikely to cause any problems, especially for larger dogs.

However, a whole packet can cause symptoms like diarrhea and vomiting in smaller dogs.

This would be cause for close observation for at least 24 hours. 

Always err on the side of caution and obtain necessary vet help if you’re concerned.

Not all dogs will react the same way to the same amount of theobromine.

Their size, activity, individual sensitivity, and overall health can affect how your dog’s body handles theobromine.

Doggy says, consider reading this too: What to do if my dog ate Babybel wax?

What Should I Do if My Dog Ate M&Ms?

When you notice that your dog may have consumed M&Ms, the first and most important thing to do is stay calm.

Panic helps no one!

Follow the tips below to handle the situation the right way.

Assess the situation

Take a minute to assess the situation and the scene.

Can you determine the quantity of M&Ms consumed vs. the size of your dog?

If your dachshund has devoured a family pack of M&Ms, it’s fairly safe to say you should run, not walk, to the vet. 

Did your great Dane nibble one or two M&Ms?

Probably worth keeping an eye on him for signs of symptoms, but not necessary to rush off the emergency vet just yet, unless you see symptoms developing within 24 hours.

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Take immediate action

With theobromine poisoning, the sooner you seek treatment for symptoms, the better.

If you’re concerned, the first thing to do is to call your vet.

Calmly provide as much information as possible – your dog’s breed, weight, and the amount of M&Ms you think were consumed.

He or she will help you to determine your next course of action. 

You may be required to induce vomiting if it’s serious enough, and I don’t recommend you do this unless you’re specifically instructed to.

Inducing vomiting should only ever be done under professional guidance. 

In some cases, your vet may administer activated charcoal to prevent further absorption of theobromine in your dog’s body.

Activated charcoal can bind to toxins in the stomach, reducing their effects.

And in all likelihood, you will be asked to monitor your dog for symptoms and provide supportive care.

This may mean giving your dog medication to control symptoms and close observation to spot any complications early.

Frequently Asked Questions (FAQs)

Are peanut M&Ms toxic to dogs? 

Peanut M&Ms are a common culprit of chocolate poisoning in dogs. In just one cup (170g) of this popular candy, you’ll find 184mg of theobromine. That’s enough to cause poisoning symptoms in a small to medium dog.

Is sugar-free chocolate toxic to dogs?

Sugar-free chocolate has the added danger of potentially containing xylitol which is also extremely toxic to dogs. Always check food labels for xylitol (and sweetener used as a sugar replacement in many foods) and store the food in a safe place where your dog cannot get hold of it.

Is dark chocolate toxic to dogs?

All chocolates are toxic to dogs, and dark chocolate has a higher theobromine content than milk chocolate. That said, it’s always better to avoid your dog getting hold of any chocolate at all.

In Conclusion: My Dog Ate M&Ms

It’s super important to remember that chocolate is toxic to dogs in all its many forms.

While M&Ms are not as dangerous as dark chocolate or baking chocolate, they can still pose a serious risk if consumed in large quantities. 

If you ever find yourself in a situation where you suspect your dog has consumed M&Ms or any chocolate product, you must act quickly and calmly.

Contact your vet as soon as possible and provide as much detail about the situation as you can. 

Of course, prevention (as much as it’s possible) is always infinitely better than cure, so ensuring you keep your M&M stash well out of reach of your dog is the best solution!

Got a minute? Check out these other dog care articles too:

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Zack Keithy
Zack Keithy

Hey, I'm Zack, the Chief Editor here. I was formerly a Certified Veterinary Technician (CVT) for a good 6 years before moving on to greener pastures. Right now, I am still heavily involved in dog parenting duties, and it is my desire to share all our knowledge with fellow dog owners out there! Connect with me on LinkedIn, or read more about Canine Care Central!

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