Call ASPCA Poison Control: (888) 426-4435 or go to your nearest emergency vet. Do not wait for symptoms to appear.
Caffeine is a methylxanthine compound toxic to dogs, related to theobromine found in chocolate. Dogs metabolise caffeine much more slowly than humans — what feels like a mild stimulant to a person can cause seizures, cardiac arrhythmias, and death in a dog. Sources include coffee, espresso, tea, energy drinks, caffeine tablets, pre-workout supplements, and some medications.
Great Danes are the largest dog breed by height and among the heaviest. Their enormous body weight means they need a much higher absolute dose of any toxin before crossing clinical thresholds — but this also means a single ingestion can be a very large absolute quantity. They have extremely high rates of bloat (GDV) and dilated cardiomyopathy, both of which interact dangerously with many toxins.
Why Does Breed Matter for Caffeine Toxicity?
Toxic doses for caffeine are calculated per kilogram of body weight. A Great Dane typically weighs 50–90 kg, which directly determines how much caffeine (methylxanthine) their body is exposed to relative to their size. Beyond weight, Great Danes have specific traits — outlined in the breed profile above — that can affect how quickly symptoms develop, how severe they become, and what complications to watch for.
When you call Poison Control, always give your dog's exact current weight, not a breed average. Even within the Great Dane breed, a significant weight difference changes the risk calculation meaningfully.
How Much Caffeine Is Toxic to a Great Dane?
These thresholds are based on the typical Great Dane weight range of 50–90 kg. Always use your dog's actual weight for the most accurate estimate. Use our Caffeine Toxicity calculator to enter your dog's exact weight.
| Dog weight | Mild signs | Serious signs | Potentially fatal |
|---|---|---|---|
| 50 kg (small Great Dane) | 750 mg of caffeine | 2.0 g of caffeine | 7.5 g of caffeine |
| 68 kg (average Great Dane) | 1.0 g of caffeine | 2.7 g of caffeine | 10 g of caffeine |
| 90 kg (large Great Dane) | 1.3 g of caffeine | 3.6 g of caffeine | 14 g of caffeine |
ℹ️ Mild signs at ~15mg/kg; serious at 40mg/kg; potentially fatal at 150mg/kg+. A standard espresso contains ~63mg caffeine — enough to cause symptoms in a 4kg dog. Source: ASPCA Animal Poison Control Center dose thresholds. Always confirm with your vet.
Symptoms of Caffeine Poisoning in Great Danes
Symptoms typically appear within 1–2 hours of ingestion. Watch for:
Due to Great Dane-specific traits noted above, pay particular attention to abdominal bloating or unproductive retching, which in a Great Dane can indicate GDV — a life-threatening secondary emergency on top of poisoning.
What to Do If Your Great Dane Ate Caffeine
- Stay calm and note how much they ate — estimate the amount and type of caffeine and your dog's weight. This information is critical for the vet.
- Call ASPCA Poison Control immediately — (888) 426-4435. Available 24/7. A $95 consultation fee may apply, but they will advise whether you need emergency care.
- Do not induce vomiting unless specifically instructed by a vet or Poison Control. Inducing vomiting incorrectly can cause additional harm.
- Go to an emergency vet if symptoms are already present, if a large amount was consumed, or if Poison Control advises it. Find a 24-hour emergency vet near you.
- Bring the packaging of the food or substance if possible — ingredient lists help the vet calculate exact toxin exposure.
Special Considerations for Great Danes
Great Danes with GDV or cardiomyopathy face compounded risks from toxic ingestion. If your Dane is showing signs of a distended abdomen alongside other poisoning symptoms, treat GDV as a co-emergency and say so when calling Poison Control. Their sheer size can make physical examination and decontamination more logistically challenging for vets.
Frequently Asked Questions
Tea contains less caffeine than coffee but is still toxic. Green tea and black tea both contain caffeine, and some herbal teas contain other stimulants. All should be kept away from dogs.
A small lick from a small spill is unlikely to cause serious harm in a large dog. However, in small dogs, even a few laps of brewed coffee can approach concerning levels. Call Poison Control to assess the specific risk.
Very much so — energy drinks contain high caffeine concentrations combined with other stimulants. They are among the most dangerous caffeine sources for dogs.
Treatment involves inducing vomiting if recent ingestion, IV fluids, medications to control heart rate and prevent seizures, and monitoring. Most dogs recover with prompt treatment.