Advance directives are written documents that tell your doctors what kind of treatment you'd like to have if you become unable to make medical decisions (e.g., if you're in surgery, or in a coma, or you have a progressive illness such as dementia or Alzheimer’s). It's a good idea to an advance directive and a health care power of attorney before you are very ill. There are two types of written advance directives.

A durable power of attorney for health care (sometimes called a durable medical power of attorney) specifies whom you've chosen to make medical decisions for you. It is activated any time you're unconscious or unable to make medical decisions. You need to choose someone who meets the legal requirements in your state for acting as your agent. Most states disqualify anyone under the age of 18, your health care provider, or employees of your health care provider from serving as your agent.

Living wills or Health Care Declarations are a kind of advance directive that come into effect when a person is terminally ill. A living will does not give you the opportunity to select someone to make decisions for you, but it allows you to specify the kind of treatment you want in specific situations. For example, you might choose to specify that you do not want to be treated with antibiotics if death is imminent.

When writing an advance directive you should consider the kind of care you want and the kind of care you don’t want. This includes if you want antibiotics, or if you want to be kept alive on a machine. Your health care provider should have a copy of your advance directive and you should discuss your wishes with your loved ones and your power of attorney.