What Is Severe Autism?

Also known as level 3 autism, it is the most severe form

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Severe autism, known as level 3 autism in diagnostic criteria, is autism with high support needs. It often means the autistic person is nonverbal or has very limited speech and restricted social communication skills.

Autism with these intense traits also often comes with sensory processing issues and extreme difficulty dealing with changes in routine. Common behavioral challenges include aggression, running or wandering away, and self-injury.

Autistic people with high support needs experience profound challenges and require very substantial assistance. They are often unable to live independently and require 24-hour-a-day care.

This article discusses autism with high support needs, its traits, and its challenges. It also explains the therapies available for autistic people with high support needs and how to find help for caregivers.

Other Names for Severe Autism

  • Classic autism
  • Kanner's autism (after the person who first described it)
  • Profound autism
  • Low-functioning autism (but this term is not used by most in the autism community)
  • Autism with high support needs (often preferred by people in the autism community)

Traits of Autism With High Support Needs

There are three levels of autism when it's diagnosed. Level 1 describes people considered more independent with lower support needs, and level 3 describes autistic people living with intense traits and high support needs. Level 2 is somewhere in between.

Some autism traits are common to all levels, while others are typically only present in autistic people with high support needs.

To be diagnosed with autism, these traits must affect daily life, and level 3 autism traits have the greatest impact in this regard. They lead to the most significant levels of disability and challenge, which is why round-the-clock support and supervision are usually needed.

Level 3 autism symptoms

 Illustration by Theresa Chiechi for Verywell Health

Speech and Social Skills

Everyone diagnosed with an autism spectrum disorder (ASD) has a difficult time with social skills and communication.

Autistic people with high support needs are most likely to be nonverbal, or entirely unable to use spoken language. They may also appear not to notice the people around them.

Sensory Dysfunction

Many autistic people have traits of sensory dysfunction. That means they're either too sensitive (or not sensitive enough) to:

  • Light
  • Smell
  • Sound
  • Touch
  • Taste

Autistic people also can struggle with "hidden" sensory systems in the body, including:

  • Interoception: Internal body cues like hunger, thirst, needing to use the toilet, and response to ambient temperature
  • Proprioception: The sense of self-movement, action, force, and location
  • Vestibular: Balance, spacial orientation, and coordination

Autistic people with high support needs tend to be extremely sensitive, to the degree that crowded, bright, or noisy environments can be overwhelming. Sensory overload can lead to an autistic meltdown.

Cognitive Challenges

Many autistic people have high IQs. But some have IQs at or near 75, the cutoff for intellectual disability. Generally speaking, autistic people with high support needs tend to have low to very low IQs, even when tested using non-verbal testing tools.

It's important to know, however, that appearances can be deceiving. Some people with intense autism traits still learn to communicate. They may use sign language, spelling boards, or other tools like augmentative and alternative communication (AAC) devices.

Some people diagnosed at level 3 are quite articulate. They prove that at least some autistic people with high support needs are more capable than they may appear.

Repetitive Behaviors

Most autistic people engage in repetitive behaviors and self-stimulatory behaviors. Those with low support needs may flap their hands, rock, or flick their fingers, but they can often control these behaviors for a period of time when necessary.

Autistic people with high support needs are likely to have many such behaviors, and those behaviors can be intense and uncontrollable. Common ones are violently rocking, door slamming, and moaning.

Physical Traits

Autistic people with high support needs may have symptoms of other disorders that occur more often in people with their intense autism traits. These may include:

  • Sleeplessness
  • Epilepsy
  • Gastrointestinal issues

Because of the autistic person's communication difficulties, such issues can go undetected or undiagnosed. An undiagnosed physical illness can lead to physical pain, which may cause or worsen behavioral issues.

Challenges in Level 3 Autism

When autistic people with high support needs engage in intense behaviors, it may be because these behaviors stem from frustration, sensory overload, or physical pain.

Sometimes, people with intense autism traits may express themselves through frightening behaviors. If the behaviors can't be managed, they can become dangerous.

It's possible that, in some cases, it's not safe for family members to live with an autistic teen or adult.

Self-Injury

While self-injury can occur among autistic people with lower support needs, behaviors such as head-banging and pica (eating non-food items) are far more common among autistic people with high support needs.

Aggressive Behaviors

Aggression is relatively rare in autism. But it's certainly not unheard of, particularly among people with more intense autism traits or those with co-occurring conditions like severe anxiety.

People with level 3 autism may act out by hitting, biting, or kicking. They may also have behaviors, such as fecal smearing or door banging, that require a quick and effective response.

Wandering

It's common for autistic people with high support needs to wander off or run away. Often, there's no obvious cause and no intended destination. This is sometimes called eloping.

Making the situation worse, people living with intense autism traits generally don't have the tools to communicate with first responders.

This can put the autistic person in dangerous situations. In some cases, special locks, alarms, and identification tools are necessary to keep them from eloping or becoming lost in the community.

Treatment for Autism With High Support Needs

Autism isn't curable. However, many medical and non-medical treatment options can help autistic people living with intense traits. Some approaches are more common sense than anything else.

Using Medications

Treatments for autistic people with high support needs usually include medications for anxiety and related issues. Anti-psychotic drugs and antidepressants can also be effective.

It's important to carefully monitor the autistic person's responses to drugs. Side effects or negative interactions can cause as many problems as they solve.

Incorporating Non-Medical Therapies

Autistic children with high support needs often respond well to applied behavior analysis (ABA), a form of behavioral therapy often provided free by schools and early intervention programs.

Sensory integration therapy can be helpful for addressing serious sensory challenges. Other useful therapies include:

Applied Behavioral Analysis

Applied behavioral analysis (ABA) is considered a "gold standard" of autism therapy, yet it remains controversial due to its reliance on behavior modification principles and techniques. Some autism advocates reject the ABA approach of erasing autism traits through reward, finding it harmful. Despite ABA successes, it is sometimes seen as disrespectful to neurodivergent people.

Checking for Physical Issues

Few autistic people with high support needs are able to describe physical symptoms or problems. So, it's a good idea to regularly check for underlying physical health issues that may be causing unwelcome behaviors or making them worse.

It's not uncommon, for example, to discover that a child's apparently aggressive behavior is actually a response to severe gastrointestinal pain. That pain may go away with the right dietary changes.

Once the pain is gone, they usually find it much easier to relax, engage, learn, and behave appropriately.

Teaching Communication Skills

Even if someone with intense autism traits learns to use spoken language, they may have a hard time asking or answering questions. They may also repeat sounds without assigning meaning to them.

Communication, of course, is the key to any kind of engagement and learning. Many of those same people who cannot speak are able to communicate through the use of sign language, picture cards, digital talking boards, and keyboards.

Creating the Right Environment

Sensory issues can be minimized by creating a highly structured and low-stress environment. Things that may help an autistic person with high support needs include:

  • A very regular routine
  • Low lights
  • Few loud noises
  • Predictable foods

Support for Caregivers

Parents and caregivers of autistic people with high support needs often have a lot on their plate. Caregiver burnout is common.

It is important to learn to make time for yourself. Taking care of your emotional, physical, and social needs is crucial for caregivers.

Support services are often available and may include:

  • Caregiver support meetings (either for level 3 autism or all levels of autism)
  • Family care and case management to guide you through healthcare, education, and legal systems
  • Online support boards
  • One-on-one therapy or counseling
  • Parent coaching
  • Respite care to give you a much-needed break

In the United States, autism support services are often administered through the state or county health department. Search online for your state's department of autism services.

Summary

Autism with high support needs, diagnosed as level 3, means someone is living with intense autism traits. They may be nonverbal and be unable to engage with people. Sensory stimuli may be overwhelming. Cognitive differences are common. Repetitive behaviors may be intense and uncontrollable.

These traits can make for significant challenges such as self-injury, aggressive behaviors, and eloping.

Treatment includes medications and additional therapies (physical therapy, speech therapy). With time and effort, a person diagnosed with level 3 autism may be able to communicate.

When someone in your life has autism with high support needs, it can help to educate yourself about autism and how it's treated and managed. Work closely with the healthcare team, and they can help you to learn coping skills for day-to-day life.

Frequently Asked Questions

  • How do you know if an autistic person has high support needs?

    Someone with level 3 autism has intense and noticeable traits. That said, only a clinician can make a formal autism diagnosis.

  • Do autism traits become more intense with age?

    It's unlikely that new autism traits will arise with age, though they can worsen without intervention and/or as life circumstances change.

  • Can level 3 autism get better?

    Autism cannot be cured, and support for autistic people living with intense traits will always be needed. However, treatment can help a person better manage their autism.

6 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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Lisa Jo Rudy

By Lisa Jo Rudy
Lisa Jo Rudy, MDiv, is a writer, advocate, author, and consultant specializing in the field of autism.