Star Healer is a 1985 science fiction book by author James White, part of the Sector General series.
[1] Conway is replaced on the ambulance ship Rhabwar by Diagnostician Prilicla.
Conway visits healer Khone on the planet Goglesk, and witnesses first-hand their destructive racial mass-hysteria response to physical proximity.
Conway also proposes staving off geriatric Hudlar problems by elective amputation.
At the end, he successfully delivers a sentient telepathic Unborn (seen in the other novel of the series Ambulance Ship) from its violent non-sentient Protector.