A number of practices at the end of life can causally contribute to diminished consciousness in dying patients. Despite overlapping meanings and a confusing plethora of names in the published literature, this article distinguishes three types of clinically and ethically distinct practices: (1) double-effect sedation, (2) parsimonious direct sedation, and (3) sedation to unconsciousness and death. After exploring the concept of suffering, the value of consciousness, the philosophy of therapy, the ethical importance of intention, and the rule of double effect, these three practices are defined clearly and evaluated ethically. It is concluded that, if one is opposed to euthanasia and assisted suicide, double-effect sedation can frequently be ethically justified, that parsimonious direct sedation can be ethically justified only in extremely rare circumstances in which symptoms have already completely consumed the patient's consciousness, and that sedation to unconsciousness and death is never justifiable. The special case of sedation for existential suffering is also considered and rejected.
Keywords: Double effect; End-of-life; Ethics; Euthanasia; Palliative; Sedation.