Self-injury can be one of the most distressing and difficult behaviours that parents, carers, family members and people with autism themselves may face. Here we give an overview of self-injurious behaviour, possible causes and interventions.

Sometimes referred to as self-harm, self-injurious behaviour is any activity in which a person inflicts harm or injury on themselves. About half of people with autism engage self-injurious behaviour at some point in their life. It can take many different forms, including:

  • head banging (on floors, walls or other surfaces)
  • hand or arm biting
  • hair pulling
  • eye gouging
  • face or head slapping
  • skin picking, scratching or pinching
  • forceful head shaking.

People across the spectrum and of all ages may engage in self-injurious behaviours at some point. People who engaged in self-injurious behaviours as children may return to these as adults during times of stress, illness or change.

Usual behavioural intervention approaches are not always appropriate. Seek professional guidance for any self-injurious behaviour which is difficult to manage or resistant to intervention, or for any behaviour which places the person at risk of harm.


The reasons a person engages in self-injurious behaviours can be wide and varied, and will often involve a complex interaction between multiple factors. People with learning disabilities told Self-Injury Support that they self-injure when:

  • they feel they are not listened to 
  • they have been told off
  • they have little or no choice about things
  • they have been bullied 
  • they are involved in arguments, or hear other people arguing 
  • they are feeling unwell
  • they have memories of a bereavement
  • they have memories of abuse.

In July 2016 Spectrum news reported on an online survey which found a higher rate of self-harming in autistic men and women than other people.

Medical or dental problems

People with autism may have difficulty communicating to others that something is wrong physically and particular self-injurious behaviours (such as ear slapping or head banging) may be their way of coping with pain or communicating discomfort.

Mental health issues

Some self-injurious behaviour may indicate underlying mental health issues such as depression or anxiety.

Repetitive behaviour

Repetitive behaviours, obsessions and routines are common in people with autism, and some forms of self-injury may be expressions of this feature.

Developmental stages

Some self-injurious behaviour may be persisting remnants of earlier motor behaviours which occur during particular developmental periods (eg hand mouthing which may continue beyond infancy).


Sudden self-injurious behaviour can get a very quick response from other people, and many such behaviours occur in people who have no other functional way of communicating their needs, wants and feelings. 

  • Head slapping, or banging the head on a hard surface, may be a way of communicating frustration, getting a preferred object of activity, or reducing demands.
  • Hand biting may help someone cope with anxiety or excitement.
  • Skin picking or eye gouging may be a response to lack of stimulation or boredom.

Learned behaviour

The person may learn that self-injurious behaviour can be a very powerful way of controlling the environment. A behaviour (eg head slapping) which was initially a response to physical pain or discomfort could eventually become a way of avoiding or ending an undesired situation (eg turning the television off, interrupting an argument taking place nearby).

Preventative strategies

Here are some ideas about how to prevent self-injurious behaviours. 

Rule out medical and dental causes

Visit the GP or dentist and seek a referral to a specialist if needed. Bring along notes about when the behaviour happens (ie what time of day and in which situations), how often it happens, when it first started, and how long it lasts.

Think about the function of the behaviour

Complete a behaviour diary, which records what is occurring before, during and after the behaviour, or a functional analysis questionnaire, to help you to understand the purpose of the behaviour. Make notes on the environment, including who was there, any change in the environment and how the person was feeling.

Increase structure and routine

Establish a clear daily routine to increase predictability and thereby reduce anxiety. Try to build a range of activities into the person's routine to minimise boredom and restrict opportunities for the person to engage in self-injurious behaviour. Make plans for difficult times of the day. Increase structure and provide additional supervision and support to the person during these periods or activities. People with Pathological Demand Avoidance may need a less directive and more flexible approach than others on the autism spectrum.

Provide sensory opportunities

Find alternative activities that provide a similar sensory experience and build these into the daily routine. Jumping on a trampoline or swinging on a swing may provide needed stimulation to the vestibular system (that head shaking or slapping may have previously provided). Providing the person with a bum bag of edible or safe objects to chew on that provide different sensory experiences such as gum, carrots, raw pasta or sultanas may reduce the need for hand or arm biting.

Introduce communication tools

Support the person to use other ways of communicating their wants, needs and physical pain or discomfort, eg by using visual supports such as pictures of body parts, symbols for symptoms, or pain scales, pain charts or apps.

Reward appropriate behaviours

Provide frequent encouragement to the person for engaging in appropriate behaviour and for periods in which they did not engage in the self-injurious behaviour. This will help the person learn that other, more appropriate behaviours bring positive outcomes.

Rewards can take the form of verbal praise and attention, preferred activities, toys, tokens or sometimes small amounts of favourite foods or drinks. Ensure that you clearly name the behaviour that you are rewarding, eg "Jane, that's good waiting!" and ensure that rewards are provided immediately after the behaviour that you wish to encourage eg "You can spend 10 minutes on the computer now".

It should be noted that some people with autism do not enjoy social attention. In these circumstances, verbal praise can cause distress and actually stop the person engaging in the desired behaviour in the future.


Medication may help to reduce the frequency of self-injurious behaviour for some people. As with physical restraints, medication should be seen as a last resort approach to management and again, should never be used without teaching new skills and consulting a medical specialist.

Reactive strategies

Appropriate responses will vary according to the behaviour, but here are some pointers on what to do when the behaviour is happening. It is important when using any of these strategies that the person is also provided with opportunities to develop skills to communicate their needs more appropriately and to self-regulate stress and anxiety levels.

Respond quickly

Intervene early, and respond quickly and consistently to incidents of self-injury. Even if the behaviour serves the function of gaining attention from others, it is never appropriate to ignore severe self-injurious behaviour.

Keep responses low key

Limit verbal comments, facial expressions and other displays of emotion, as these may inadvertently reinforce the behaviour. Try to speak calmly and clearly, in a neutral and steady tone of voice.

Reduce demands

The person may be finding a task too difficult or that they are unable to complete the activity at that time. Come back to the activity again later when the person is feeling calmer.

Remove physical and sensory discomforts

Remove unpleasant sensory input. Provide relief for physical discomfort (eg pain killers) if a medical professional has advised this after seeing the person.


Tell the person what they need to do instead of the self-injurious behaviour, eg "David, hands down". Use visual cues such as picture symbols to back up instructions. Redirect to another activity that is incompatible with the self-injury (eg an activity that requires both hands) and provide praise and reinforcement for the first occurrence of appropriate behaviour, eg "David, that's excellent playing with your train".

Provide light physical guidance

If the person is having difficulty stopping the behaviour, provide light physical guidance, eg gently guide their hand away from their head, using as little force as possible. Immediately try to redirect attention to another activity and be prepared to provide physical guidance again if the person attempts to re-commence self-injurious behaviour. This approach must be used with extreme caution as it may escalate the behaviour or cause the person to target others.

Use barriers

Place a barrier between the person and the object that is causing harm. For head slapping, place a pillow or cushion between the person's head and their hand. For hand or arm biting, provide an alternative object to bite down on. For head banging on a hard surface, place a cushion or pillow between the surface and the person's head. You can get removable padding that is placed temporarily on the floors or walls to minimise injury. You can find products such as soft furniture and "safe rooms" at Link Design and Safespaces.

Consider physical restraints

Some self-injurious behaviour can place the person at serious risk of harm. In these instances, it may be appropriate to explore the use of physical restraints such as arm restraints, gloves or helmets. These may also reduce the sensory experience and frequency of the behaviour.

However, physical restraints are very restrictive and should always be used under the guidance of a specialist to ensure they are used safely and appropriately, and with a plan to fade out their use over time.

Physical restraints do not address the cause of the behaviour, so they must never be used in isolation without teaching the person new skills which address the function of the behaviour.

Call for help

In extreme circumstances or emergencies, call 999 for assistance.

Further information


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Last reviewed 03 October 2016.