Dogs may be able to detect a specific scent associated with epileptic seizures in humans, according to a small study in Scientific Reports. The preliminary results suggest that seizures may be anticipated in the future, using their odour characteristics.

Previous research has shown that diseases such as breast or lung cancer are associated with specific changes in bodily odours. However, the possibility that epileptic seizures, which are individual-specific and highly variable, may also be reflected in an odour profile had not been tested.

Amelie Catala and colleagues presented three female and two male trained dogs with complex odours (breath and bodily odour) obtained from epileptic patients during a seizure, outside a seizure and following an exercise session. Each dog was involved in nine trials in total, during which the dogs were presented with seven cans. Only one can in each trial contained the seizure odour. The dogs’ ability to detect positives (sensitivity) ranged from 67% to 100%, while their ability to correctly identify negatives (specificity) ranged from 95% to 100%.

The results suggest that, despite the variety of seizures and individual body odours, seizures are associated with specific odour profiles. These characteristics could potentially be used in future to anticipate seizures and allow patients to seek a more secure environment. However, further studies need to determine the chemical properties of the seizure odour, and if it is present before a seizure occurs.