A Health Care Power of Attorney empowers an Agent to make important health care decisions for you in the event that you lose the ability to make these decisions for yourself. For example, if you are unconscious, comatose, mentally incompetent, or otherwise unable to make decisions, a Health Care Power of Attorney comes into effect, and the Agent can then make decisions on your behalf regarding your medical treatment according to prior agreement. Also referred to as "Advanced Health Care Directives," Health Care Powers of Attorney give instruction on what you want to happen to you in the future, in the event that you become unable to give such instructions. Note that after you have executed a Health Care Power of Attorney, you are still entitled to make health care decisions for yourself as long as you are mentally able to do. The Power of Attorney only becomes effective after you lose the ability to make decisions for yourself.
In many states, the Health Care Power of Attorney may also express whether you desire "life-sustaining procedures," in the event that you enter a permanent coma or become terminally ill. Living Wills, another kind of advanced health care directive, also allow you to express your wishes concerning life-sustaining procedures, but they are different from Health Care Powers of Attorney in that this is all they allow. The Health Care Power of Attorney concerns this and all other health care decisions, and is therefor the more robust and inclusive document.