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.
Border Collies carry the MDR1 (ABCB1) gene mutation at higher rates than most breeds, which impairs the blood-brain barrier's ability to exclude certain drugs and toxins. This means some substances — including common antiparasitic medications and certain sedatives used in treatment — can cause severe neurological toxicity in Border Collies even at doses safe for other breeds. This gene mutation is critical to disclose to your vet.
Why Does Breed Matter for Caffeine Toxicity?
Toxic doses for caffeine are calculated per kilogram of body weight. A Border Collie typically weighs 12–20 kg, which directly determines how much caffeine (methylxanthine) their body is exposed to relative to their size. Beyond weight, Border Collies 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 Border Collie breed, a significant weight difference changes the risk calculation meaningfully.
How Much Caffeine Is Toxic to a Border Collie?
These thresholds are based on the typical Border Collie weight range of 12–20 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 |
|---|---|---|---|
| 12 kg (small Border Collie) | 180 mg of caffeine | 480 mg of caffeine | 1.8 g of caffeine |
| 16 kg (average Border Collie) | 240 mg of caffeine | 640 mg of caffeine | 2.4 g of caffeine |
| 20 kg (large Border Collie) | 300 mg of caffeine | 800 mg of caffeine | 3.0 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 Border Collies
Symptoms typically appear within 1–2 hours of ingestion. Watch for:
Due to Border Collie-specific traits noted above, pay particular attention to neurological signs — seizures, disorientation, or dilated pupils — which the MDR1 mutation can make more severe in Border Collies.
What to Do If Your Border Collie 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 Border Collies
Border Collies with the MDR1 gene mutation require a vet who knows about this — it affects which antidotes and support medications are safe to use. If you don't know your Border Collie's MDR1 status, inform the vet anyway and request that MDR1-sensitive drugs be avoided until testing can be done. This is not a minor detail in a poisoning scenario.
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.