Is Marshmallows Toxic to Cats and Dogs?
Regular marshmallows are not toxic to dogs or cats, but the sugar causes stomach upset, sticky pieces are a choking hazard, and sugar-free versions containing xylitol are dangerous to both species.
Usually minor, but watch for symptoms.
Usually minor, but watch for symptoms.
In an emergency, do not wait.
Medical disclaimer: This tool is for general information only and isnot a substitute for veterinary diagnosis or treatment. Toxicity depends on the amount, your pet’s size, and health history. If your pet may have ingested something harmful, contact your veterinarian or a poison control hotline ((888) 426-4435 / (855) 764-7661) immediately — do not wait for symptoms to appear.
What is Marshmallows?
Regular marshmallows are not toxic to dogs or cats, but the sugar causes stomach upset, sticky pieces are a choking hazard, and sugar-free versions containing xylitol are dangerous to both species.
Also known as: marshmallow, sugar-free marshmallows, fluff, marshmallow creme.
Symptoms to Watch For
🐕 In Dogs
- Stomach upset
- Vomiting or diarrhea from the sugar load
- Choking on a large or sticky marshmallow
- Pancreatitis risk if eaten in quantity or by a small dog
🐈 In Cats
- Stomach upset
- Vomiting or diarrhea
- Choking on sticky candy
What to Do If Ingested
- Remove remaining marshmallows from reach.
- Check the label: if it is sugar-free and lists xylitol (also called birch sugar), treat as an emergency — call a vet or poison hotline immediately.
- For one or two regular marshmallows, offer water and monitor.
Steps apply to both cats and dogs. When in doubt, call a vet or poison hotline before acting. Have a cat? Run the Pet Poison Triage Wizard for cat-specific steps.
When to Call the Vet Immediately
Call your veterinarian or a poison control hotline right away if you notice any of these:
- The marshmallows were sugar-free and contain xylitol
- A large quantity was eaten, especially by a small dog
- Vomiting, diarrhea, or abdominal pain develops
- Gagging or difficulty swallowing after a large marshmallow
Frequently Asked Questions
Frequently Asked Questions
Can dogs have regular marshmallows as a treat?
A plain marshmallow will not poison a dog, but it is a poor treat choice: it is almost entirely sugar with no nutritional value. Small dogs can choke on the sticky texture, and repeated sugary treats contribute to obesity and pancreatitis risk. If you want a soft training treat, a tiny piece of plain cooked chicken beats a marshmallow every time.
Why are sugar-free marshmallows an emergency?
Sugar-free marshmallows are often sweetened with xylitol, which is highly toxic to dogs even in small amounts — it triggers a rapid insulin release that can cause life-threatening low blood sugar within 10–60 minutes, and larger doses can damage the liver. Check any "diet" or "keto" marshmallow label for xylitol or birch sugar before it ever reaches the campfire bag.
My cat stole a mini marshmallow. Should I worry?
One regular mini marshmallow is not toxic to cats — expect at most a brief stomach upset. Confirm it was not a sugar-free version containing xylitol, which is dangerous for cats too. Watch for vomiting over the next day, and call a vet if your cat vomits repeatedly, stops eating, or seems lethargic.
What about marshmallows roasted over a campfire?
The roasted part adds the same problems in a hotter, stickier package: burned sugar can irritate the mouth and throat, and molten marshmallow is an easy way for a dog to burn its tongue or choke. Keep roasting sticks and s'mores supplies well above nose level, and count sticks — a discarded skewer is a separate puncture hazard.
Sources
This entry is reviewed against the following authoritative veterinary sources.
Last reviewed: 2026-10-20