Atharvaveda 8.10.29

8.10.29

sód akrāmat sā́ sarpā́n ā́gachat tā́ṃ sarpā́ úpāhvayanta víṣavaty éhī́ti |
tásyās takṣakó vaiśaleyó vatsá ā́sīd alābupātráṃ pā́traṃ |
tā́ṃ dhr̥tárāṣṭra airāvató 'dhok tā́ṃ viṣám evā́dhok |
tád viṣáṃ sarvā́ úpa jīvanty upajīvanī́yo bhavati yá eváṃ véda ||29||

She ascended; she came to the serpents; the serpents called to her: O poisonous one, come! of her Takshaka descendant of Viçāla was young, the gourd-vessel [was] vessel; her Dhṛitarāshṭra son of Irāvant milked; from her he milked poison; upon that poison the serpents subsist; one to be subsisted upon becometh he who knoweth thus.