Over half a million mice were killed as part of Botox experiments in Ireland over a four year period.
That's according to campaign group the Irish Anti-Vivisection Society who are calling for the practice to be banned.
Pharmaceutical companies used over 500 thousand rodents to batch test new products between 2017 and 2021.
They were injected with different substances to determine the point where the dosage killed half of the test subjects.
The IAVS have described the process as a "gratuitous abuse of animals in laboratories".
