Yes. You can change the document at any time. It is a good idea to review your advance directive each year to be sure it still says how you want to be treated and names an advocate you trust.
This article is intended to be helpful and informative. But even common legal matters can become complex and stressful. A qualified estate planning lawyer can address your particular legal needs, explain the law, and represent you in court. Take the first step now and contact a local estate planning attorney to discuss your specific legal situation.