People aged 16 or over are entitled to consent to their own treatment. This can only be overruled in exceptional circumstances.
Like adults, young people (aged 16 or 17) are presumed to have sufficient capacity to decide on their own medical treatment, unless there's significant evidence to suggest otherwise.
Children under the age of 16 can consent to their own treatment if they're believed to have enough intelligence, competence and understanding to fully appreciate what's involved in their treatment. This is known as being Gillick competent.
Otherwise, someone with parental responsibility can consent for them.
This could be:
A 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.
By law, healthcare professionals only need 1 person with parental responsibility to give consent for them to provide treatment.
In cases where 1 parent disagrees with the treatment, doctors are often unwilling to go against their wishes and will try to gain agreement.
If agreement about a particular treatment or what's in the child's best interests cannot be reached, the courts can make a decision.
In an emergency, where treatment is vital and waiting for parental consent would place the child at risk, treatment can proceed without consent.
If a young person refuses treatment, which may lead to their death or a severe permanent injury, their decision can be overruled by the Court of Protection.
This is the legal body that oversees the operation of the Mental Capacity Act (2005).
The parents of a young person who has refused treatment may consent for them, but it's usually thought best to go through the courts in this situation.