Consent is the principle that a person must give their permission before they receive any type of medical treatment. Consent is required from a patient regardless of the type of treatment being undertaken, from a blood test to an organ donation.

The principle of consent is one of the cornerstones of medical ethics. It is also enshrined (held sacred) in international human rights law.

What constitutes consent?

For consent to be valid, it must be voluntary and informed, and the person consenting must have the capacity to make the decision. These terms are explained below.

• Voluntary: the decision to consent or not consent to treatment must be made alone, and must not be due to pressure by medical staff, friends or family.
• Informed: the person must be given full information about what the treatment involves, including the benefits and risks, whether there are reasonable alternative treatments, and what will happen if treatment does not go ahead.
• Capacity: the person must be capable of giving consent, which means that they understand the information given to them, and they can use it to make an informed decision.

There are a few exceptions when treatment can go ahead without consent (see Consent to treatment - how it works).

One main exception is if a person does not have the mental capacity (the ability to understand and use information) to make a decision about their treatment. In this case, the healthcare professionals can go ahead and give treatment if they believe that it is in the person’s best interests.

Legal terms

This article mentions several legal terms and acts of parliament, which are explained below.

• The Mental Health Act (1983) sets out various legal rights that apply to people with severe mental health problems. The act also contains the powers which, in extreme cases, enable some people with mental health problems to be compulsorily detained in hospital.
• The Mental Capacity Act (2005) is designed to protect people who cannot make decisions for themselves. The act explains when a person is considered to be lacking capacity, and how decisions should be made in their best interests. 
• The Court of Protection is the legal body that oversees the operation of the Mental Capacity Act (2005).
• An advance decision (previously called an advance directive) is a legally binding document that sets out in advance the treatments and procedures that someone does or does not consent to.

For more information about the legal issues surrounding someone’s care, see the Carers Direct information about the Mental Capacity Act (2005). 

Under the terms of the Mental Capacity Act (2005), all adults are presumed to have sufficient capacity (the ability to use and understand information to make a decision) to decide on their own medical treatment unless there is significant evidence to suggest otherwise.

The evidence has to show that:

• a person's mind or brain is impaired or disturbed, and
• the impairment or disturbance means that the person is unable to make a decision at the current time

Examples of impairments or disturbances in the mind or brain include:

• mental health conditions, such as schizophrenia (a condition that causes hallucinations and delusions) or bipolar disorder (manic depression – when your moods swing from one extreme to another)
• dementia (an ongoing decline of mental abilities, such as memory and understanding)
• serious learning disabilities
• long-term effects of brain damage
• physical or mental conditions that cause confusion, drowsiness or a loss of consciousness
• delirium (mental confusion)
• intoxication caused by drug or alcohol misuse

Someone is thought to be unable to make a decision if they are unable to:

• understand information about the decision
• remember that information
• use that information as part of their decision-making process, or
• communicate their decision by talking, using sign language or by any other means

If someone makes a decision about treatment that most people would consider to be irrational, it does not constitute a lack of capacity if the person making the decision understands the reality of their situation.

For example, a person who refuses to have a blood transfusion because it is against their religious beliefs would not be thought to lack capacity. This is because they understand the reality of their situation and the consequences of their actions.

However, someone with anorexia (an eating disorder) who is severely malnourished yet rejects treatment because they refuse to accept that there is anything wrong with them, would be considered incapable. This is because they do not understand the reality of their situation.

Changes in capacity

Your capacity to consent can change. For example, you may have the capacity to make some decisions but not others, or your capacity may come and go.

In some cases, people can be considered capable of deciding some aspects of their treatment but not others. For example, a person with severe learning difficulties may be capable of deciding on their day-to-day treatment, but incapable of understanding the complexities of their long-term treatment.

Some people with certain health conditions may have periods when they are capable and periods when they are incapable. For example, a person with schizophrenia may have periods when they are considered capable, but they may also have psychotic episodes (when they cannot distinguish between reality and fantasy) during which they are not considered capable.

Your capacity can also be temporarily affected by:

• shock
• panic
• fatigue (extreme tiredness)
• medication

If you know that your capacity may change, you can make an 'advance decision’ (previously known as an advance directive), stating how you would like to be treated in case of future incapacity (see the box to the right).

If a person specifically states in their advance decision that they do not want to undergo a particular treatment, this is legally binding. The only exception may be if that person is being held under the Mental Health Act (1983). This is an act that allows some people with mental health problems to be compulsorily detained in a psychiatric hospital.

The Directgov website has more information about mental health and the Mental Health Act (1983).

Mental
Mental refers to the processes in the mind.

Hallucinations
Hallucinations are a sensory experience in which a person sees, hears, or feels something or someone that isn't really there.

Delusions
Where you believe things that are untrue.

The seeking and giving of consent should not be a one-off event. It should be a continual process of communication between yourself and your healthcare providers.

If you are going to have major medical intervention, such as an operation, your consent should be obtained well in advance so that you have plenty of time to study any information about the procedure. You should also have the chance to ask as many questions as you want.

Additional procedures

There may be some circumstances when, during an operation, it becomes obvious that you would benefit from an additional procedure that was not included in your original consent.

For example, you may be having abdominal surgery when your surgeon notices that your appendix is infected, dangerously close to bursting and needs to be removed.

If is felt that it would be too dangerous to delay the additional procedure and wake you up to get your consent, the additional procedure can go ahead if it is considered to be in your best interest.

However, extra procedures cannot be done just because it would be convenient for the healthcare professionals treating you. There has to be a clear medical reason why it would be unsafe to wait to obtain your consent.

Emergency treatment

If you require emergency treatment to save your life, and you are unable to give consent as a result of being physically or mentally incapacitated (for example, you are unconscious), treatment will be carried out. Once you have recovered, the reasons why treatment was necessary will be fully explained to you.

Giving consent

Consent should be obtained from the healthcare professional who is directly responsible for your current treatment. This could be:

• a nurse who is arranging a blood test
• a GP who is prescribing new medication for you
• a surgeon who is planning your operation

Consent can be given:

• verbally
• non-verbally – for example, you may raise your hand to indicate that you are happy for a nurse to take a blood sample
• in writing – by signing a consent form

A signed consent form by itself does not constitute consent; it simply serves as evidence of consent. The consent form will not be valid if your consent is:

• not voluntary
• not informed, or
• you do not have enough mental capacity (the ability to use and understand information to make a decision) to give consent

See Consent to treatment - capacity for more information about capacity and situations that can affect your capacity. 

Refusing treatment

If you have enough capacity and make a voluntary and informed decision to refuse a particular treatment, your decision must be respected. This is still true even if your decision would result in your death, or the death of your unborn child.

You are still entitled to receive any other appropriate medical treatment and care that is felt would be in your best interest. However, if you ask for a course of treatment that healthcare professionals believe would not be in your best interest, they have no obligation to provide it.

Children and teenagers

Teenagers who are 16 and 17 years old are entitled to consent to their own treatment, and this consent cannot be overruled by their parents.

Children who are under 16 years old can consent to their own treatment if it is thought that they have enough intelligence, competence and understanding to fully appreciate what is involved in their treatment.

If a child who is under 16, or a teenager who is 16 or 17 years old, refuses treatment and by doing so this may lead to their death or a severe permanent injury, their decision can be overruled by the courts. The court used is the Court of Protection, which is the legal body that oversees the operation of the Mental Capacity Act (2005).

In some cases, the parents of a child who has refused treatment have been allowed to consent for them. However, it may be best to go through the courts in such situations.

Parental responsibility

If a child who is under 16 does not have the capacity to consent, someone with parental responsibility can consent for them. See the box (left) for a list of people who can hold parental responsibility. The person with parental responsibility must have the capacity to give consent.

If a parent refuses to give consent to a particular treatment, this decision can be overruled by the courts if treatment is thought to be in the best interests of the child.

If one person with parental responsibility gives consent and another does not, the healthcare professionals can accept the consent and perform the treatment. If the people with parental responsibility disagree about what is in the child’s best interests, the courts can make a decision. 

In an emergency, where treatment is vital and waiting to obtain parental consent would place the child at risk, treatment can proceed without consent.

Exceptions

There are a number of exceptions where a capable person can be treated without first obtaining their consent. These exceptions are listed below.

• Under the Public Health (Control of Disease) Act (1984), a magistrate can order that a person is detained in hospital if they have an infectious disease that presents a risk to public health – such as rabies, cholera and anthrax.
• Under the National Assistance Act (1948), a person who is severely ill or infirm and is living in unsanitary (unclean) conditions can be taken to a place of care without their consent.
• Under the Mental Health Act (1983), people with certain mental health conditions, such as schizophrenia, bipolar disorder or dementia can be compulsorily detained at a hospital or psychiatric clinic without their consent.

Prisoners

The legal rights of prisoners are unaffected when it comes to the issue of consent. No capable prisoner can be treated without consent even if that means their life will be at risk. This includes a prisoner who is refusing to eat food.

Abdomen
The abdomen is the part of the body between the chest and the hips.

Appendix
The appendix is a narrow muscular pocket in the abdomen that has no known function. It is attached to the large intestine.

Bipolar disorder
Bipolar disorder, previously known as manic depression, is a condition that affects your moods, which can swing from one extreme to another.

Dementia
An ongoing decline of mental abilities, such as memory and understanding.

Schizophrenia
Schizophrenia is a chronic (long-term) mental health condition that causes a range of different psychological symptoms, including psychotic episodes.

Consenting to treatment is not always straightforward, and a number of issues can arise. These are explained below.

Withholding information

In order to consent to a treatment or procedure, you need to be fully informed about the treatment and understand why it is considered necessary. 

Healthcare professionals should not withhold information just because it may upset or unnerve you. Even if you specifically request not to be told about the extent or likely outcome of your condition, the healthcare professional has a moral and legal responsibility to provide you with at least:

• a basic overview of your condition
• the likely outcome of your condition
• your treatment options

Similarly, you will be refused any request to a healthcare professional to withhold information about a relative or friend’s condition, due to worries that it may upset them.

Mental health conditions

People with conditions that are covered by the Mental Health Act (1983), such as schizophrenia or bipolar disorder, may not have the capacity (the ability to use and understand information to make a decision) to give consent. However, this should not be taken for granted, and it needs to be assessed at the time that consent is required.

The person’s preferences should be investigated and their agreement to treatment should be sought whenever they are able to make a rational decision. These wishes should be respected if the person cannot give proper consent later on.

If the person lacks capacity and has not previously expressed their wishes, their mental health condition may be treated without consent, as may any related conditions. For example, those resulting from self-harm. Unrelated physical conditions cannot be treated without consent.

An advanced decision (previously known as an advanced directive) prohibiting certain types of treatment can be overruled if you are being held under the Mental Health Act (1983), even if you made the advanced decision when you were capable. See Consent to treatment - capacity for more information about advance decisions. 

The Directgov website has more information about mental health and the Mental Health Act (1983).

Self-harm and attempted suicide

In cases of self-harm or attempted suicide where the person refuses treatment and was competent when they harmed themselves, it may be necessary to see if they can be treated without consent under the Mental Health Act (1983). This can happen if a person has a serious mental health condition that requires hospital treatment.

The person's nearest relative or an approved social worker must make an application for the person to be forcibly kept in hospital and treated. Two doctors must assess the person's condition.

If a person is kept in hospital under the Mental Health Act (1983), it does not automatically mean that they cannot agree to treatment. However, they will need to be reassessed to see whether they are capable of making an informed decision.

If a person has tried to harm themselves but does not have a mental disorder covered by the Mental Health Act (1983), unwanted treatment cannot be forced upon them. However, efforts to offer treatment must be made.

Adults without capacity

If an adult lacks capacity, any physical interventions must be in their 'best interests'. The healthcare professionals must:

• consider if it is safe to wait until the person can give consent
• involve the person in the decision as much as possible
• determine whether the person has previously expressed any opinions regarding certain procedures, perhaps on the grounds of religious or moral beliefs
• if possible, consult other people, such as the person’s immediate family

If the person has made an advance decision (see Consent to treatment - capacity) about the matter, the healthcare professionals cannot override this decision whatever the consequences. An advance decision can only be overruled if it is regarding treatment for a mental health condition and the person is being held under the Mental Health Act (1983).

In situations where there is doubt about what is in the person’s best interests, the healthcare professionals can refer to the Court of Protection, which is the legal body that oversees the operation of the Mental Capacity Act (2005).

Life-prolonging treatments

There are rules governing when life-prolonging treatment can be withheld or withdrawn when consent is not available.

The relatives and friends of the person receiving the treatment, along with the healthcare professionals responsible for the person’s care, should decide whether treatment should be continued. They should consider whether:

• the treatment is in the best interests of the person (in terms of quality of life and how long they will live) 
• how much the treatment is improving their condition

It is important to note that there is a difference between stopping a patient's artificial supply of water and nutrients, and taking a deliberate action to make them die, for example, by injecting a lethal drug. The latter is illegal.

If activity in the brain has stopped, it is known as brain stem death. In this case, all treatments can be stopped. See the Health A-Z topic about Brain death for more information about this condition.

Court decisions

There are some circumstances where a decision should always be referred to the Court of Protection if the person cannot or will not give their consent. Situations that should always be referred to the courts include:

• sterilisation (a permanent procedure that causes sterility) for contraceptive purposes
• donation of regenerative tissue, such as bone marrow (the spongy material found in the hollow centres of some bones)
• withdrawal of nutrition and hydration from a person who is in a persistent vegetative state (when they are technically conscious but have no sense of awareness) See the Health A-Z topic about Vegetative state for more information
• where there is serious concern about the person's capacity or best interests