Autism in adults may present with different symptoms than in children. Many adults learn to live with the symptoms, and this can make diagnosis difficult.

Autism spectrum disorder (ASD) is one of the most common neurodevelopmental disorders. In most cases, autistic people receive a diagnosis in childhood, usually after the age of 4 years. However, some autistic adults are not diagnosed in childhood, even if their symptoms are more severe.

For an autistic person not diagnosed in childhood, receiving an ASD diagnosis later in life may be helpful for many reasons. In particular, it can provide better access to services and support. In this article, we discuss the signs and symptoms of ASD in adulthood and what to do if a person would like a diagnosis.

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Autistic people may find some aspects of communication and social interaction challenging. They may have difficulty relating to people and understanding their emotions. Autistic adults may also have inflexible thought patterns and behavior, and may carry out repetitive actions.

Common signs and symptoms of ASD in adults can include:

  • difficulty making conversation
  • difficulty making or maintaining close friendships
  • discomfort during eye contact
  • challenges with regulating emotions
  • extreme interest in one particular topic
  • frequent monologues on the same subject or subjects
  • hypersensitivity to sounds or smells that do not seem to bother others
  • involuntary noises, such as repetitive throat clearing
  • difficulty understanding sarcasm or idioms
  • lack of inflection when speaking
  • limited interest in only a few activities
  • preference for solitary activities
  • problems reading the emotions of others
  • trouble understanding facial expressions and body language
  • reliance on daily routines and difficulty dealing with change
  • repetitive behaviors
  • social anxiety
  • superior abilities in a particular field, such as mathematics or other disciplines
  • the need to arrange items in a specific order

Autistic people will not usually have all the above signs and symptoms, and they may experience others that are not on the list.

There may be some similarities between ASD and other disorders, such as attention deficit hyperactivity disorder (ADHD), but the signs and symptoms of ASD vary from person to person.

Also, the symptoms can differ across genders. Some people may seem able to cope better with social situations than others, as their symptoms may be more subtle and masked. As a result, it can be more challenging to diagnose ASD.

Seeking an ASD diagnosis as an adult can be challenging for several reasons:

  • People who did not receive a diagnosis in their younger years may have milder symptoms, which can be more difficult to recognize. At times, such people may never get a diagnosis.
  • If people have been living with ASD for some time, they may be better at masking the signs and symptoms.
  • Research shows that one of the common diagnostic tests for autism in adulthood, the ADOS-2, may be fairly reliable. But a doctor needs to recognize a person’s symptoms in order to refer them to testing.

Is there a test for ASD in adults?

Clinicians have developed different tests that can help diagnose ASD in adults. These include diagnostic tests such as ADOS 2 Module 4, ADI-R, and 3Di Adult.

However, it is not clear how reliable these tests are for adults. The reasons for this include:

  • Researchers who look at the reliability of ASD tests often use a small number of study participants.
  • Not many research studies on testing for adult ASD include enough participants from historically underserved groups, such as People of Color or people who are LGBTQIA+. This means the results of studies looking at ASD testing methods may not represent a true population of autistic adults.
  • Many clinicians may not be familiar with the signs of ASD in adulthood. This is especially true if the patient’s symptoms are not severe or if the patient also has other conditions, for example, anxiety.

Autistic people may have higher rates of co-occurring conditions, such as anxiety or depression, than those in the general population.

How to begin a diagnosis process

Adults who suspect they or a loved one might be autistic can do a self-assessment test for adults. A person can find these tests online. While they cannot give a diagnosis, the tests are a good starting point.

A person seeking a diagnosis can take the results of such a test to a primary care doctor who will try to determine whether ASD may be present by:

  • enquiring about the symptoms, both current and during childhood
  • observing and interacting with the person
  • speaking to a loved one (with permission)
  • checking for other physical or mental health conditions that may be causing symptoms

If no underlying physical condition can explain the symptoms, the doctor may refer the person to a psychiatrist or a psychologist to make an ASD diagnosis.

If symptoms are not present in childhood but begin in adolescence or adulthood, this may indicate a cognitive or mental health condition other than ASD.

It may be difficult to find a specialist who can diagnose ASD in adults. Individuals who would like a diagnosis for themselves or a loved one may need to do research to find a provider with experience diagnosing autistic adults.

Another option is to speak to a developmental pediatrician or child psychiatrist who is willing to see adult clients.

Benefits of diagnosis

Not every undiagnosed autistic adult may want or need a diagnosis. It is important to respect the needs and preferences of the individual. For those who prefer it, a diagnosis may offer several advantages.

  • It may provide an explanation for the challenges an autistic individual may be experiencing.
  • It may give family members, friends, and colleagues a better understanding of ASD.
  • It may open up access to services and benefits, including in the workplace or education environments.
  • It may replace an incorrect diagnosis, such as ADHD.

Living with ASD may be hard for some autistic adults. They may struggle with social interactions, get fixated on routines, or experience sensitivities to light or sound.

Many of the same symptoms that appear in autistic children may also exist in adults. But adults experiencing these symptoms may find it difficult to live independent, day-to-day lives as a result.

A study on services and outcomes in autistic adults showed that 27% of autistic participants were unemployed. Autistic adults may also have more limited options for support services than autistic children. In the same study, 25% of autistic participants reported not getting enough support services.

Some autistic adults experience high intelligence, strong memory, an ability to think “outside the box,” and strong talent in particular areas. Other traits can include a unique sense of humor, and a strong sense of fairness and justice.

For many autistic people, ASD is an essential part of their identity and does not require support. For those autistic adults who experience more challenges, increased access to the following may help:


Learning more about autism can give autistic individuals and their loved ones or carers a greater understanding of the condition.

It can also help an autistic person feel validated and find solutions that work for them.

Friends and family can help reduce stress and be more compassionate by accessing available learning opportunities, many of which are free.


As with neurotypical people, autistic people may benefit from seeing a therapist if they are experiencing anxiety, work stress, or feelings of isolation.

Therapists can introduce autistic people to methods such as cognitive behavioral therapy. This may help with challenges that may be more particular to ASD, such as having rigid thoughts. Therapy may take place either individually or in a group or family setting.

Taking steps to improve mental health inequity can also help underserved autistic adults get the counseling they may need.

Vocational rehabilitation

Vocational rehabilitation can help autistic people cope with career-related challenges. It allows them to explore the possibility of further education, volunteering, or job changes.

Some autistic people may find their workplaces uncomfortable if they are too noisy, too bright, or require a long commute.

Employers can take steps to support neurodiversity in the workplace, for example, by making appropriate accommodations for autistic employees. Many resources are available, including from the Employer Assistance and Resource Network on Disability Inclusion.

Autistic people can thrive in the right workplace and with adequate support.

Peer support

Some autistic people may find it helpful to connect with other autistic people who may be experiencing similar things. A person can do this through online groups and forums, or at face-to-face support meetings.

Interacting with other autistic adults may give an autistic person new ideas about things they can do in their own lives. It can also expose a person to more resources.

Many autistic people advocate for taking a more active role in their own support services. A growing body of evidence shows that access to autistic peers can positively benefit an autistic person’s life.


Medications cannot cure ASD. But certain prescription medications may alleviate some co-occurring symptoms, such as depression and anxiety.

The Food and Drug Administration (FDA) has approved only a few medications for helping with ASD-specific symptoms in children. Adults should consult with a healthcare professional before trying any medication.

For some autistic people, getting a diagnosis of ASD in adulthood can provide relief, validation, and access to some support services for those who require them. For others, a diagnosis may not be necessary.

Adults who suspect that they may be autistic and would like a diagnosis should speak with their doctor, who can provide advice and guidance on the next steps.

As awareness of ASD in adulthood increases, finding the right support services and doctors who can recognize the signs and symptoms should become easier.