Pervasive Developmental Disorder

Medically Reviewed By William C. Lloyd III, MD, FACS
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What is pervasive developmental disorder?

Pervasive developmental disorder is a type of autism. The full name for this disorder is pervasive developmental disorder not otherwise specified (PDD-NOS). In the past, health experts viewed it as a separate subtype of autism. As of 2013, PDD-NOS is now part of autism spectrum disorder (ASD). ASD is a group of developmental disorders. ASD also includes classic autistic disorder and Asperger syndrome.

The Centers for Disease Control and Prevention (CDC) estimates that 1 in 68 American children has ASD. ASD occurs in both genders, but boys are more likely to have it than girls. ASD also appears in all ethnicities, socioeconomic levels, and geographic areas.

Like all forms of autism, PDD-NOS occurs with a spectrum of symptoms and severity. People on the high end of the spectrum tend to function with fewer challenges compared to those on the low end.

People with ASD have social, communication, language and behavioral problems. In PDD-NOS, social and language problems are more pronounced.

There are three basic subgroups of symptoms of PDD-NOS:

  • High-functioning PDD-NOS accounts for about 25% of cases. This group is similar to Asperger syndrome, but the individual has delays in language and cognition (thinking, problem-solving, planning). This is usually not the case with Asperger syndrome.

  • In another 25%, symptoms resemble classic autistic disorder. However, people in this group do not fully meet the diagnostic criteria for classic autistic disorder.

  • The largest group—50%—meets the diagnostic criteria for autism. However, people in this group have very mild or no symptoms of behavioral problems.

Health experts do not fully understand what causes ASD, including PDD-NOS. There is also no cure for ASD at this time. Fortunately, a variety of therapies and other treatments are available to help people with ASD and their families.

Seek prompt medical care if your child has symptoms of ASD, such as delays in normal development or lack of social skills. Sometimes, people with ASD, including PDD-NOS, can exhibit aggressive behavior. Seek immediate medical care (call 911) if someone with ASD becomes violent, threatening, or dangerously aggressive, or is hurting himself or herself.

What are the symptoms of pervasive developmental disorder?

Symptoms of autism spectrum disorder (ASD), including pervasive developmental disorder not otherwise specified (PPD-NOS) begin early in life. Parents of children with PDD-NOS may notice symptoms in their child’s infancy. Diagnosis usually occurs by age three. Specific symptoms vary in nature and severity from person to person.

Communication and language symptoms of PPD-NOS

Many people with PDD-NOS have a hard time communicating with others. They may display the following symptoms:

  • Delays in using and understanding language

  • Difficulty relating to other people

  • Does not understand or use nonverbal communication skills, including facial expressions and gestures

  • Has one-sided conversations or struggles with reciprocal conversation

  • Interprets what other people say very literally, and does not easily understand jokes or irony

  • Lacks eye contact during communication

  • Speaks repetitively or with unusual speech patterns

  • Tends to talk about themselves and not others

Social and sensory symptoms of PDD-NOS

People with PDD-NOS have social habits that cause them problems in everyday life. This includes:

  • Abnormal sensitivity or insensitivity to the way things look, feel, sound, taste or smell

  • Attachment to certain objects

  • Dislike of physical contact

  • Inability to maintain eye contact

  • Inability to play using imagination

  • Lack of empathy, which is the ability to understand other people’s feelings

  • Obsessive interest in a specific topic, such as planes or music

  • Solitary play and social isolation. Children with PDD-NOS often have difficulty making friends.

Behavioral symptoms of PDD-NOS

People with PDD-NOS may display the following behaviors:

  • Attachment to routines and inability to cope if things happen outside the routine

  • Awkward movements or delay in motor development

  • Difficulty controlling emotions or displaying emotions at inappropriate times

  • Extreme impulsivity and hyperactivity

  • Odd mannerisms

  • Repetitive body movement or behaviors

  • Self-abusive behaviors such as head banging and biting

  • Unusual play with toys

Serious symptoms that might indicate a life-threatening condition

In some cases, a child or adult with ASD, including PDD-NOS, can become violent and pose a danger to herself or others. Seek immediate medical care (call 911) if someone with ASD has any of these symptoms:

  • Suicidal thoughts or a desire to hurt oneself or others

  • Violent or threatening behavior

What causes pervasive developmental disorder?

Health experts do not fully understand what causes autism spectrum disorder (ASD), including pervasive developmental disorder not otherwise specified (PDD-NOS). It is likely many factors contribute to its development. Many researchers believe differing levels of brain abnormalities play a role. Other possibilities include the use of medications during pregnancy, other medical conditions present at birth, viral infections during pregnancy or infancy, and chromosomal abnormalities.

Health experts do know ASD is the result of a biological process. The specific deficits and the odd behaviors and expressions are not due to poor parenting practices.

In the past, many people wondered whether childhood vaccines were linked to ASD. Research from the Centers for Disease Control and Prevention (CDC) and the Institute of Medicine (IOM) shows that vaccines do not cause ASD. These organizations also emphasize the health benefits of vaccines outweigh any risks from them.

What are the risk factors for PDD-NOS?

Researchers have identified certain risk factors that increase the likelihood of developing PDD-NOS, including:

  • Genetic conditions, such as Down syndrome and fragile X syndrome
  • Having a sibling with ASD
  • Having older parents—a mom 35 or older or a dad 40 or older at the time of birth
  • Male gender

How is pervasive developmental disorder treated?

There is no cure for autism spectrum disorder (ASD), including pervasive developmental disorder not otherwise specified (PDD-NOS). However, several therapies can help a child’s development and interactions. In PDD-NOS, each person has unique symptoms and challenges. Therefore, a personalized treatment plan is necessary. The goals of treatment are specific for each person. They may include language development, learning social skills, and helping improve focus and attention span.

A child’s family, doctors, therapists and educators should work together on a plan that offers the best chance of success. In general, treatment is more successful the earlier it begins after diagnosis.

Behavioral, educational and physical therapies

Therapy can help people with PDD-NOS refine their social and communication skills, adapt to changes in their environment and learn everyday life skills. Therapies include:


Medications can reduce the severity of certain symptoms, such as anxiety, hyperactivity, aggression, and mood swings. Medications include:

  • Anti-anxiety and antidepressant medications can help minimize anxiety and mood swings
  • Antipsychotic medications can help individuals with serious behavioral problems, such as violent tendencies
  • Stimulants, such as the type doctors prescribe for attention deficit disorders

Other therapies

Other effective therapies may include dietary changes, massage therapy, and alternative medicines.

What are the potential complications of pervasive developmental disorder?

With time, many symptoms of PDD-NOS can improve. However, if a person does not receive adequate treatment or support, complications can include: 

  • Anxiety
  • Chronic stress
  • Depression
  • Disability
  • Increasingly disruptive behaviors and habits, which makes it difficult to function in school or in the workplace
  • Lasting effects of self-injury

If you need help with an ASD diagnosis or treatment, search for an autism specialist in your area.

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Medical Reviewer: William C. Lloyd III, MD, FACS
Last Review Date: 2020 Oct 29
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THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the site. If you think you may have a medical emergency, immediately call your doctor or dial 911.
  1. Autism Fact Sheet. National Institute of Neurological Disorders and Stroke.
  2. Autism Spectrum Disorder. National Institute of Mental Health.
  3. Autism Spectrum Disorder (ASD). Centers for Disease Control and Prevention.
  4. PDD-NOS. Autism Speaks.
  5. Pervasive Developmental Disorder. Medscape.
  6. Pervasive Developmental Disorders. National Institute of Neurological Disorders and Stroke.
  7. Vaccines Do Not Cause Autism. Centers for Disease Control and Prevention.