The Most Commonly Misdiagnosed Symptoms of Autism in Adults

Autism Spectrum Disorder persists into adulthood; this is a medical fact, yet few doctors know how to recognize and diagnose autistic symptoms in adults. Here are some of the condition’s most common warning signs, and the other conditions they are mistakenly attributed to.

By Eileen Bailey Verified Updated on July 14, 2022

Scribbles on a wall signifying the many hard-to-read signs of autism in adults

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Before receiving a diagnosis of autism spectrum disorders (ASD), many adults are misdiagnosed with a variety of conditions, according to the Asperger/Autism Network. These misdiagnoses stem, in part, from widespread unfamiliarity with the signs and symptoms of autism in adults, particularly those who were never evaluated or diagnosed in childhood.

Though it’s true ASD may present alongside other comorbid or coexisting conditions, these ancillary diagnoses are not always relevant or helpful, as many symptoms are better explained by the diagnosis of ASD.

The following are symptoms or characteristics of ASD commonly (and mistakenly) attributed to other conditions:

Difficulty with social interactions, which is one hallmark symptom of ASD, may be attributed to shyness, social anxiety disorder, or avoidant personality disorder.
Difficulty with self-expression, both verbal and non-verbal, or with quickly processing what other people are saying can be misdiagnosed as a language-based learning disability.
Autistic people are five times more likely to be picky eaters with narrow food choices and ritualistic eating behaviors, according to a study completed in 2013. This may sometimes be attributed to an eating disorder.
Autistic adults might have a hard time connecting and relating to other people or find it difficult to see things from another person’s perspective, which may be misconstrued as a personality disorder.
Autistic adults commonly exhibit repetitive or ritualistic behaviors, for example rocking back and forth and eating only certain foods, according to a study published in 2015. These behaviors might be seen as symptoms of obsessive compulsive disorder. Sometimes these behaviors, especially when done in public, are seen as eccentric or odd, or the person may be mislabeled as schizophrenic.
Autistic adults might continue to struggle to manage their emotions. They may have sudden outbursts of anger or become withdrawn when overwhelmed. These emotional reactions, which are common in those with ASD, might be seen as neuroticism, borderline personality disorder, or another mental illness. Outside of a medical realm, these behaviors might also be misinterpreted as selfishness or immaturity.
Some autistic people prefer solitude. They may find social interactions draining and spend time pursuing solitary activities. Or, they may have difficulties with social interactions and find it easier to be alone. But many people do not understand the preference for solitude, and may see it instead as a mood disorder.
Autistic adults might be hypersensitive, for example, refusing to eat certain foods because of the texture, becoming irritable in high-stimulus situations, or bristling when touched. This behavior may be misdiagnosed as sensory processing disorder.
When adults with ASD become irritable or tense during transitions or if there is a change in routine, they may be diagnosed with generalized anxiety disorder.
ASD and attention deficit hyperactivity disorder (ADHD or ADD) share a number of symptoms, such as problems with executive functioning, impulsiveness, and hyperactivity. Occasionally, individuals with ASD are misdiagnosed with ADHD.

[Self-Test: Could You Have Symptoms of Autism Spectrum Disorder?]

ASD is a spectrum disorder, meaning symptoms can range from mild to severe. There is no laboratory test to indicate whether a patient has ASD, therefore, it is diagnosed based on behavior. And each person may experience symptoms differently. Because of this, ASD is often difficult to diagnose in adults. In addition, many doctors are familiar with autistic symptoms in children, but not in adults. Behaviors should be looked at holistically, that is all of your symptoms and behaviors should be considered rather than diagnosing based on one or two behaviors while overlooking others. If you believe you may have ASD, talk with your doctor or ask for a referral to a specialist in your area.