Part of the range of questions asks did India use poison on their weapons?
The answer is
certainly yes since the reference
https://books.google.com.om/books?id...&f=falsestates that Alexander encountered this when Indian troops fired poisoned arrows using viper and cobra poison. As alluded to by Jens the moral code at the time forbade the use of these toxins on weapons since Hindu Laws of Manu and the Brahmin and higher Castes prohibited it.
And
certainly no; if consideration is given to the fact that a lot of myth and legend is built into the chronicles of his campaign.