New Study: Even Untrained Dogs May Smell a Seizure in a Stranger

# New Study: Even Untrained Dogs May Smell a Seizure in a Stranger

*A University of Milan study published this week found that ordinary dogs — with no training and no exposure to epilepsy — could spontaneously pick out the scent of a seizure from a stranger’s sweat. Here’s what the science actually shows, and what it means for service-dog work.*

If you’ve ever wondered whether dogs just *know* when something is wrong, a new study gives that instinct some real scientific weight. Researchers at the University of Milan found that untrained dogs could detect the scent of a seizure from sweat samples collected from a complete stranger — no prior exposure to epilepsy, no medical-detection training, nothing.

The study was published in the *Annali dell’Istituto Superiore di Sanità* (Annals of the Italian National Institute of Health) and reported by ScienceAlert on October 31, 2026.

## What the researchers did

The setup was simple and carefully controlled. The team collected sweat samples from a single volunteer — a 6-year-old girl with epilepsy who was not hospitalized — during a seizure, and again six hours before and after the seizure. They also prepared a sterilized gauze control with no human scent at all.

Thirty dogs of various breeds, none of whom had ever met the patient or been exposed to epilepsy, were then given two minutes to freely investigate three odor stations. Neither the handlers nor the observers knew which station held which sample — a double-blind design.

The result: **14 of the 30 dogs approached the seizure sample first** — about 40% more often than you’d expect by chance. And notably, the dogs showed no signs of distress, fear, or anxiety while investigating.

## What it means — and what it doesn’t

This is genuinely exciting, but let’s be precise about what was proven:

**What it shows:** Seizures appear to produce a distinct olfactory signature in human sweat — one strong enough that even dogs with zero training can pick it out. This lines up with earlier work: a 2019 University of Rennes study (Catala et al., published in *Scientific Reports*) found that five *trained* dogs identified seizure sweat samples with 67–100% sensitivity and 95–100% specificity.

**What it doesn’t show:** This was *detection*, not *prediction*. The dogs identified a scent sample from a seizure that was happening — they weren’t forecasting one before it started. The study also used one patient’s scent, so we don’t yet know how well the finding generalizes, and a lab setting is very different from real-world alerting.

## The important distinction: instinct isn’t the same as a service dog

Here’s where this matters for our community. It’s tempting to read this study and think, “My dog senses my seizures — that makes them a service dog.” The science says the sensing part may well be real. But under the Americans with Disabilities Act (28 CFR 35.104), a service animal is a dog **individually trained to do work or perform tasks** for a person with a disability. An untrained dog that seems to sense something wrong is not a service dog under the law — no matter how remarkable its nose is.

That distinction protects everyone: it preserves full public-access rights for genuinely trained teams, and it keeps the focus where it belongs — on training.

## What seizure-response service dogs actually do

A trained seizure-response dog performs specific, reliable tasks, such as:

– **Alerting** a handler or another person that a seizure is beginning
– **Staying with** the handler during the seizure to provide comfort and grounding
– **Fetching help** or activating an alert device
– **Positioning** themselves to cushion a fall or prevent injury
– **Retrieving medication** or a phone after the seizure ends

These are trained behaviors — practiced hundreds of times until they’re dependable in chaotic, real-world conditions. That’s the difference between a fascinating instinct and a working service dog.

## Frequently asked questions

**Can an untrained dog detect seizures?**
This study suggests dogs may spontaneously recognize the scent of a seizure, even without training. But spontaneous interest in a scent is not the same as a reliable, trained alert behavior.

**Does this mean my pet is a seizure-alert dog?**
Not under the law. A pet that seems sensitive to your condition is wonderful — but a service dog is defined by individual training to perform specific tasks (28 CFR 35.104). If you need a working seizure-response dog, talk to a qualified trainer or service-dog organization.

**What tasks do seizure-response service dogs perform?**
Alerting before or at the onset of a seizure, staying with the handler during the event, fetching help or medication, cushioning falls, and activating emergency devices.

**How long does training take?**
Professional service-dog training typically takes 1–2 years, including task-specific training and public-access proofing. Owner-training is legally permitted in the U.S. but requires the same standard of reliable, trained task work.

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*Reviewed for accuracy against the published study. Last reviewed: November 1, 2026.*
*Sources: ScienceAlert (Oct 31, 2026); Annali dell’Istituto Superiore di Sanità; Catala et al. (2019), Scientific Reports; ADA regulations, 28 CFR 35.104 (ADA.gov).*

**Do you rely on a seizure-response dog?** [Register your service dog free](https://usaservicedogregistration.com/free-registration/) and explore our [psychiatric service dog resources](https://usaservicedogregistration.com/psychiatric-service-dog/).