Q: What is the Principle of Double Effect (PDE) at End of Life care?


Answer: "an action having foreseen harmful effects practically inseparable from the good effect is justifiable".

In End of Life care administering medication to relieve pain is morally justifiable despite knowing the possible bad effect i.e death, though all endeavours should be exercised to minimize the risk of the bad effect and the benefit of good action outweighs the risk of bad effect.  


Reference: 

Quill TE. Principle of double effect and end-of-life pain management: additional myths and a limited role. J Palliat Med 1998; 1:333.