Medical power of attorney allows a person to handle someone else’s health care decisions only in the chance that he or she may not be able to think for themselves. The representative may not choose any ‘end of life’ decisions unless the Principal specifically writes in that he or she would like that as an option.
A non-durable power of attorney, or a general power of attorney, does not allow the agent to act in the interests of the principal if the latter becomes incapacitated. Generally, a non-durable power of attorney grants a limited scope of action to the agent, whom the principal may simply need to carry out a single task.
A power of attorney allows an agent to act on behalf of a principal. When a principal signs and grants a power of attorney, he grants either general or limited authority to the agent. The limited (also known as "specific") power of attorney restricts the scope to the agent's activities.