Berenice had prepared a potion for herself, but at her mother's entreaty, who stood by, she gave her part of it. Both drank of the potion, which prevailed over the weaker body. But Berenice, having drunk too little, was not released by it, but lingering on unable to die, was strangled by Bacchides for haste.
Plt Lucullus Chapter 18: Death of the family of Mithridate