Section 4 MHA: Emergency Mental Health Detention Explained

Section 4 of the Mental Health Act 1983 is the emergency provision of the Act, a short-term power to detain someone in hospital for mental health assessment when a genuine emergency makes the standard two-doctor process impractical. This article explains how Section 4 works in plain language, who can authorise it, what patients and families can expect, and what happens when the 72-hour period ends.

What Is Section 4 MHA?

Section 4 MHA is the emergency admission for assessment section of the Mental Health Act 1983. It allows a person to be detained in hospital for up to 72 hours without their consent, for the purposes of psychiatric assessment, when:

The situation is an urgent emergency
Detention is necessary for the person’s own health or safety, or for the protection of others
Obtaining the two medical recommendations required under Section 2 would involve undesirable delay

How Is Section 4 Different From Section 2 and Section 3?

The three most commonly used sections of the Mental Health Act serve different purposes:

Section 2, admission for assessment, lasting up to 28 days, requiring two medical recommendations
Section 3, admission for treatment, lasting up to six months, requiring two medical recommendations
Section 4, emergency admission for assessment, lasting up to 72 hours, requiring only one medical recommendation

Section 4 is specifically designed for emergencies where the full Section 2 process cannot be completed quickly enough.

Understand Section 4 of the Mental Health Act, the emergency admission provision, how it works, how long it lasts, and what rights patients and families have.

Who Can Apply for Section 4?

Section 4 requires two roles:

One medical recommendation, ideally from a doctor who already knows the person, such as their GP. In a genuine emergency any registered medical practitioner may make the recommendation.
One application, made by an Approved Mental Health Professional (AMHP), or in some circumstances by the person’s Nearest Relative

How Long Does Section 4 Last?

Section 4 lasts for a maximum of 72 hours from the time the person is admitted to hospital. Within this period, the clinical team should assess whether continued detention is necessary and, if so, obtain a second medical recommendation to convert the Section 4 into a Section 2.

What Happens When Section 4 Expires?

Conversion to Section 2, if a second medical recommendation is obtained within the 72-hour window, the Section 4 can be converted to Section 2 (up to 28 days for assessment)
Conversion to Section 3, if the clinical picture is sufficiently clear and treatment is required, Section 3 may be considered
Discharge, if the person is assessed as no longer meeting the criteria for detention, they must be released

Patient Rights Under Section 4

Section 4 does not strip a person of their fundamental rights. Under Section 4, a person has the right to:

Know why they have been detained
Have the section papers explained to them
Have their Nearest Relative informed
Receive support from an Independent Mental Health Advocate (IMHA)
Refuse treatment in most circumstances, Section 4 does not in itself authorise treatment without consent

Does Section 4 Authorise Treatment?

Importantly, Section 4 does not automatically authorise treatment without the patient’s consent. Specific treatment provisions require additional legal authority. In practice, treatment is usually only given without consent in Section 4 if there is an immediate risk to life.

How Families Can Support Someone Detained Under Section 4

If a family member has been detained under Section 4, some practical steps include:

Ask the hospital team to explain the detention in full
Find out if your family member has an IMHA assigned to them
Clarify your rights as Nearest Relative, including the right to be kept informed
Ask about what happens after the 72 hours
Take care of your own wellbeing, an emergency psychiatric situation is stressful for the whole family

Supporting Nervous System Recovery After Crisis

Mental health crises, and the hospital admissions that sometimes follow, place enormous strain on the nervous system of both the person in crisis and their loved ones. In the aftermath, supporting nervous system recovery becomes as important as addressing the immediate mental health concern.

The nervous system reset bundle from Herba Naturalle provides a three-month herbal protocol to gently settle an overactivated nervous system, reducing inner trembling, agitation, and stress reactivity. It can be used as a complementary support alongside professional mental health care.

If you have questions about how herbal support might fit into a recovery plan, you are welcome to reach out via the contact page or review the

Support Your Body Naturally With Herba Naturalle

If any of the topics in this article resonate with you, the Herba Naturalle Bundle page offers a structured, three-step herbal protocol designed to address chronic illness at the root. The approach, developed over 30 years of clinical practice by Anjela Jeganathan, works across three healing layers:

Step 1, Digestive Reset: Restore digestive rhythm, nutrient absorption, and healthy elimination
Step 2, Surface Nervous System Reset: Calm inner restlessness, reduce stress reactivity, and settle the mind
Step 3, Smooth Muscle & Immune Lining Healing: Reduce chronic inflammation in the tissue lining surrounding organs, blood vessels, and immune pathways

Explore the full protocol at the Herba Naturalle Bundle page and find the starting point that matches your body’s needs.

Have Questions? Get in Touch

If you would like personalised guidance or have questions about herbal support for your health, you are welcome to contact Anjela directly. She offers consultations tailored to your individual health needs.