Along with other breeds vizslas may suffer from seizures/epilepsy. Dr Claire Rusbridge at Fitzpatricks Referrals provides this great information

Here is a video

Epilepsy is thought to be genetic with a complicated mode of inheritance. As part of a research project into a number of inheritable diseases the Animal Health Trust are currently asking owners to supply DNA samples from their epilepsy affected dogs in the hope that these might help to establish the genetics pattern of the disease. Cheek swab kits are available from Bryan McLaughlin at the AHT. The process is very simple and the only cost involved is postage back to the AHT. This project is completely anonymous – and you can read more about it here
Please also inform our breed health coordinator if your dog suffers from seizures/epilepsy