Poisons derived from Acokanthera plants are known to have been used in Africa as far back as the 3rd century BC when Theophrastus reported a toxic substance that the Ethiopians would smear on their arrows. The poisons derived from this genus of plants were used throughout eastern Africa, typically as arrow poisons for hunting and warfare. Acokanthera schimperi, in particular, exhibits a very large amount of ouabain, which the Kenyans, Tanzanians, Rwandans, Ethiopians, and Somalis would use as an arrow poison.
The poison was extracted from the branches and leaves of the plant by boiling them over a fire. Arrows would then be dipped into the concentrated black tar-like juice that formed. Often, certain magical additives were also mixed in with the ouabain extract in order to make the poison work according to the hunters wishes. In Kenya, the Giriama and Langulu poison makers would add an elephant shrew to the poison mixture in order to facilitate the pursuit of their prey. They had observed that an elephant shrew would always run straight ahead or follow a direct path and thought that these properties would be transferred to the poison. A poisonous arrow made with this shrew was thought to cause the hunted animal to behave like the shrew and run in a straight path. In Rwanda members of the Nyambo tribe, also known poison arrow makers, harvest the Aconkathera' plants according to how many dead insects are found under it - more dead insects under a shrub indicating a higher potency of poison. 
Although ouabain was used as an arrow poison primarily for hunting, it was also used during battle. One example of this occurred during a battle against the Portuguese, who had stormed Mombasa in 1505. Portuguese records indicated that they had suffered a great deal from the poisoned arrows.