What is NBM in Health and Social Care?

NBM is a term seen frequently in hospitals, care homes, clinics and other social care settings in the UK. NBM stands for ‘nil by mouth’, which comes from the Latin phrase ‘nil per os’. It means that a person is not allowed to eat or drink anything by mouth for a specified period. NBM includes all foods, drinks, water, and sometimes even medications, unless given by another route such as intravenously. This directive is always stated clearly in a person’s care plan or patient notes and must be followed precisely to avoid harm.

Why Might Someone Be NBM?

The NBM instruction is given for several reasons. You may hear about it in both planned and emergency healthcare settings. Some common situations include:

• Preparation for surgery or certain medical procedures
• Investigation of swallowing difficulties
• After certain types of surgery, especially involving the gut
• When a person is at risk of choking or aspiration (food or drink entering the lungs)
• While awaiting assessment and treatment for gastrointestinal problems

Let’s look at these situations in more detail. Before an operation, even under a general anaesthetic, the stomach needs to be empty. If food or drink is present, a person may vomit and inhale stomach contents during surgery, causing serious chest infections or even suffocation.

For some procedures, like scans with sedation, the digestive system also needs to be clear. After surgery, especially if the intestines or stomach are involved, the gut sometimes needs time to recover. Allowing food or drink too soon could cause pain, vomiting or slower healing.

People who have had strokes, neurological diseases or problems with their throat might be NBM because they cannot swallow safely. Aspiration results in food, drinks, or saliva entering the airway, which can cause life-threatening pneumonia. Sometimes the NBM order is temporary and lasts until a swallowing specialist can assess the person.

Who Decides if a Person is NBM?

Hospital doctors, surgeons and speech and language therapists are the main professionals who decide if NBM is needed. In social care settings, care home staff will follow medical advice, often given after a hospital visit or assessment. Sometimes, GPs or community nurses take responsibility.

The decision is always based on safety. The risk of allowing oral food or drink outweighs the benefits in these situations. For people without capacity to make this decision, the clinical team must act in their best interests, following the Mental Capacity Act 2005.

How Long Does NBM Last?

The duration varies widely. Some people may need to be NBM for a few hours before and after an operation. Others, particularly people with long-term swallowing difficulties, might be NBM for days, weeks, or longer.

Typical scenarios:

• Short NBM: Before surgery, a person may be NBM from midnight or for 6-8 hours before the procedure.
• Prolonged NBM: After complex abdominal surgery, gut injury or with severe swallowing problems, NBM status can last much longer.

The NBM status is regularly reviewed. The clinical team assesses the person and, if safe, will update the care plan to allow gradual reintroduction of foods and fluids.

What Does NBM Cover?

This is one of the most misunderstood aspects. Being NBM isn’t just about avoiding meals. The requirements are strict and include:

• No food or snacks
• No fluids, including water, tea or coffee
• No chewing gum or sucking sweets
• No oral medications (unless specified as safe)
• No ice chips (unless specifically allowed)

If medications are essential, staff may use alternative routes:

• Intravenous (through a vein)
• Intramuscular (injection in a muscle)
• Subcutaneous (under the skin)
• Rectal or as a patch

If there is ever a need to introduce sips of water, these must be clarified in writing by the doctor and specified exactly (e.g., “sips only for medication”).

Care and Support for People Who Are NBM

Caring for someone who is NBM requires careful support, monitoring, and reassurance. Being NBM can be an uncomfortable experience, especially if it lasts a long time. It can also lead to feelings of frustration or anxiety.

Physical Comfort

• Provide regular mouth care by cleaning the mouth, teeth, and lips gently with damp swabs and moisturisers.
• Use lip balms to prevent dry, cracked lips.
• Offer emotional support and explain why NBM is important for their safety.
• Keep the person upright and offer distraction, such as conversation or light entertainment, to reduce any discomfort associated with hunger or thirst.

Nutrition and Hydration

While a person is NBM, the healthcare team must be proactive in preventing dehydration and malnutrition. The body still needs nutrients and fluids, so other feeding routes may be considered.

These can include:

• Intravenous fluids (drip): Provides water and essential electrolytes
• Total parenteral nutrition (TPN): Special nutrient-rich fluids given through a vein
• Nasogastric (NG) or percutaneous endoscopic gastrostomy (PEG) feeding tubes, if swallowing remains unsafe but the gut is working
• Rectal fluids in rare circumstances

Specialist dietitians plan suitable fluid, calorie and nutrient intake.

Communication with Family and Friends

Explaining NBM to relatives and friends helps to avoid confusion and reduce the risk of well-meaning visitors offering drinks or snacks. Staff should provide clear written and verbal explanations.

Communication tips:

• Use everyday language (e.g., “no food or drink is allowed, not even sips of water, unless the doctor says it is safe”).
• Display clear NBM notices and wristbands, where appropriate.
• Update families about any changes to the NBM status as soon as they occur.

Safety Concerns and Potential Risks

The main reason for NBM is safety. Allowing food or fluid against medical advice can lead to serious, sometimes life-threatening problems.

Examples of risks if the NBM order is broken:

• Aspiration pneumonia: Food/fluid in the lungs causing infection and breathing problems
• Choking and airway blockage
• Delays in surgical or procedure times if the stomach is not empty
• Vomiting and discomfort
• Internal damage, especially after surgery on the gut

Accidental or deliberate breaking of NBM instructions must be reported promptly to senior staff or the clinical team. In these cases, the person may need additional monitoring or treatment.

Legal and Ethical Considerations

NBM is a care intervention with legal and ethical implications. The rights, wishes and preferences of the person must be respected wherever possible. Staff must always use the least restrictive option and balance safety against the risks and harms of enforced fasting.

Professional guidance and law:

• Decisions about NBM should involve the person, where possible, and follow shared decision-making principles.
• If a person lacks capacity, their best interests come first, in line with the Mental Capacity Act 2005.
• Advance decisions or statements about feeding and treatment should be respected if documented.
• Consistent documentation, clear communication, and regular review are mandatory.

Support for Staff

Caring for people who are NBM can create dilemmas. Staff may feel uncomfortable withholding food or fluids, particularly in end-of-life care or longer-term cases. Regular training, strong teamwork and clinical supervision help in these situations.

Key reminders for staff include:

• Follow instructions from the clinical team exactly
• Seek clarification if unsure about the NBM status
• Document all care provided, including mouth care and comfort measures
• Communicate changes promptly and accurately

Final Thoughts

To encapsulate, NBM stands for ‘nil by mouth’. It is a strict instruction, necessary at different times in health and social care. Reasons for NBM include preparation for surgery, preventing aspiration, recovering from operations, or undertaking specific medical investigations.

The main responsibilities for staff involved:

• Follow NBM instructions precisely
• Prevent accidental taking of food, fluids, or medications orally
• Provide regular mouth care and comfort measures
• Support nutrition and hydration using alternative routes, where required
• Keep clear and regular communication with the person and their family

Staff play a key role in making sure people are informed, comfortable, and as safe as possible during periods when NBM is required. This maintains dignity, protects health, and helps facilitate the best possible recovery or outcome.