The death of a patient taking opioids can generate strong feelings of guilt. « Have I hastened my patient's death by my administration of opioids ? » Doubts may arise in certain situations, despite the proven safety of appropriate opioid use in the management of dyspnea and pain in the palliative care setting. Fearing the harms of opioid administration, some medical practitioners may undertreat patients, forsaking them to suffering. Other doctors, desperate to relieve their excruciating suffering at all cost, may in fact have recourse to euthanizing acts. This article seeks to answer this ethical dilemma with an overview of the double effect principle.