A living will provides you with the freedom to determine how medical decisions should be made in the event you become unable or unwilling to make them for yourself. The document also allows you to appoint a health care representative to act on your behalf to carry out these wishes. Although state laws can vary, living wills generally do not expire while you are alive, absent special circumstances or your express intent.
In most states, you are free to revoke a living will by simply communicating your intentions to your healthcare provider or attending physician. However, the document also can become ineffective if it is challenged and declared invalid by a court. For example, if you failed to follow the proper requirements under state law when you created the living will, such as not having the minimum number of witnesses, a court could rule it is invalid. Also, if you designated your spouse to be your health care representative, some states automatically remove her if you get divorced, unless you specifically provide otherwise in the document.