Dreamsnake

In a world devastated by nuclear holocaust, Snake is a healer. One of an elite band dedicated to caring for sick humanity, she goes wherever her skills are needed.

With her she takes the three deadly reptiles through which her cures are accomplished: a cobra, a rattlesnake, and the dreamsnake, a creature whose hallucinogenic venom brings not healing but an easeful death for the terminally ill.

Rare and valuable is this dreamsnake. When Grass is wantonly slain, Snake must journey across perilous landscapes to find another to take its place...

Synopsis from Open Library.