Doctors, nurses and other healthcare professionals have a duty to act in what they perceive to be your best interests. But what happens if you would disagree with what they prescribe but you are incapacitated or unable to communicate?

When the Mental Capacity Act 2005 comes into force on October 1, it will introduce a power of attorney that will cover healthcare decisions and, if you are incapacitated, doctors will be legally obliged to consult a person nominated by you before and during treatment. There are also other forms of “living wills” that you can draw up to control or influence your medical treatment.

An advance statement

This is a general statement of your wishes and preferences and can reflect religious or other beliefs. Discuss your wishes with your doctor before making one: it should be in writing, signed and witnessed. Send a copy to your doctor and tell people close to you that you have made one. Advance statements are not legally enforceable and doctors adhere to them at their discretion.

You can draw one up yourself or ask a solicitor to draft one (ask for a quote before instructing anyone).

A healthcare proxy form

This appoints someone to make healthcare decisions on your behalf if you become incompetent. This person - who need not be your next of kin as long as he or she is over 18 - will be consulted by doctors when deciding your treatment plan and is responsible for informing them of your beliefs and wishes.

As with advance statements, proxy forms are not legally enforceable and doctors adhere to them at their discretion. Discuss your wishes with your doctor and your proxy; confirm the appointment in writing (signed and witnessed) and send copies to your doctor and your proxy. It is usual to find a nomination of a healthcare proxy in a pre-printed living will (see below for details) but this is something that you could draw up yourself or you could ask a solicitor to prepare a proxy form for you.

An advance directive or living will

This sets out your specific wish to refuse all or some forms of medical treatment, together with the circumstances under which this refusal will apply.

At the moment the courts normally recognise living wills as legally binding and when the Mental Capacity Act comes into force on October 1 they will be enforceable under statute as well. It is irrelevant that your refusal to receive treatment appears to be irrational to your doctor or that failure to treat you will result in your death. If your doctor ignores your living will then you (or your family on your behalf) have grounds under which to sue for compensation.

To make a living will, you must be over 18, mentally competent and not coerced, influenced or harassed into making it; you must have been fully informed about all treatment options and their implications when you made the living will; and you must not have amended it (including verbal amendments).

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