Without a medical power of attorney, Missouri law gives doctors and hospitals a default priority list for who can make decisions on your behalf—often a spouse or adult child. That might work out fine. Or it might mean someone you wouldn’t choose is deciding whether you receive aggressive treatment, get placed on life support, or enter a nursing facility. A properly drafted medical POA puts that decision in the hands of someone you trust.
Patrick Nolan of Nolan Law Firm in Kirksville, Missouri prepares healthcare powers of attorney as part of complete Missouri advance directive planning.
What Is a Missouri Medical Power of Attorney?
Missouri’s medical power of attorney—formally called a Durable Power of Attorney for Healthcare under RSMo §404.800 et seq.—is a written document appointing a healthcare agent to make medical decisions when you cannot. It is a durable document, meaning it remains effective even if you become incapacitated. It is different from a living will (which states your treatment wishes in writing)—a medical POA appoints a person to make decisions in real time as situations arise.
What Powers Does a Missouri Healthcare Agent Have?
Your healthcare agent can make most medical decisions you could make yourself, including consenting to or refusing treatment, selecting and dismissing healthcare providers, accessing medical records, and making end-of-life decisions if you have included that authority. You can limit the agent’s authority in the document—for example, prohibiting certain treatments or requiring that the agent consult with specific family members before deciding. Without explicit limits, the agent’s authority is broad.
Missouri MPOA Execution Requirements
Under RSMo §404.822, a valid Missouri medical power of attorney must be: signed by the principal (you) while mentally competent, witnessed by two adults who are not your healthcare agent, not related to you by blood or marriage, not your healthcare provider or employee, and not entitled to any part of your estate. A notary public may serve as one witness. The document does not need to be filed with any court or government agency—keep the original in a safe place and provide copies to your healthcare agent, primary physician, and any hospital where you receive regular care.
Medical POA vs. Living Will in Missouri
Missouri allows both a healthcare power of attorney and a living will (also called a declaration under RSMo §459.010). They serve different purposes. A living will contains your written instructions for specific end-of-life situations. A medical POA appoints an agent to make real-time decisions that your living will may not have anticipated. Most Missouri estate planning attorneys recommend executing both—the agent can use the living will as guidance and fill gaps it doesn’t address. See our guide on healthcare power of attorney in Missouri for a detailed comparison.
Choosing the Right Healthcare Agent
Your healthcare agent should be: someone you trust completely, someone who knows your values and medical wishes, someone who can handle stressful situations and advocate firmly with medical staff, and someone who will follow your wishes even if they personally disagree. Your agent does not need to be a medical professional or attorney—but they must be willing to take on the responsibility. Name a successor agent in case your first choice is unavailable.
When Does a Missouri Medical POA Take Effect?
A Missouri medical POA activates only when the principal lacks the capacity to make or communicate healthcare decisions—typically determined by the attending physician. The document is not continuously active. You retain full control of your own medical decisions as long as you have capacity, and the agent’s authority ends if you regain capacity.
Frequently Asked Questions: Missouri Medical Power of Attorney
What is the difference between a medical POA and a living will in Missouri?
A medical power of attorney appoints a person (your healthcare agent) to make real-time medical decisions on your behalf when you cannot. A living will contains your written instructions for specific end-of-life situations. They complement each other—most Missourians should have both, as a healthcare agent can respond to situations a living will couldn’t anticipate.
Who can witness a Missouri medical power of attorney?
Two adult witnesses are required under RSMo §404.822. Neither can be your healthcare agent, related to you by blood or marriage, your healthcare provider or their employee, or entitled to any part of your estate. A notary public may serve as one of the two witnesses.
Can I change or revoke my Missouri medical power of attorney?
Yes, at any time while you have mental capacity. You can revoke it verbally by informing your healthcare agent and physician, or in writing. Once a revocation is communicated, it is immediately effective. Creating and signing a new medical POA also supersedes the prior one.
Does a Missouri medical POA cover financial decisions?
No. A medical power of attorney covers healthcare decisions only. Financial decisions require a separate durable power of attorney for finances (a financial DPOA) under RSMo §404.705. For complete incapacity planning, Missouri residents need both documents.
What happens if I don’t have a medical power of attorney in Missouri?
Missouri’s default healthcare decision-making hierarchy applies, which typically starts with a spouse, then adult children, then parents, then siblings. If no family member is available or family members disagree, the situation may require court-appointed guardianship—an expensive, time-consuming process that could have been avoided with a simple document.
