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ADHD and ADD: Differences, Types, Symptoms, and Severity


Attention deficit hyperactivity disorder (ADHD) is one of the most common childhood disorders. ADHD is a broad term, and the condition can vary from person to person. There are an estimated 6.4 million diagnosed children in the United States, according to the Centers for Disease Control and Prevention.

The condition is also known as attention deficit disorder (ADD), though this is considered an outdated term. The American Psychiatric Association released the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) in May 2013. The DSM-5 changed the criteria necessary to diagnose someone with ADHD.

Keep reading to learn more about the types and symptoms of ADHD.

Types of ADHD

There are three types of ADHD:

1. Inattentive

This is what is typically referred to when someone uses the term ADD. This means a person shows enough symptoms of inattention (or easy distractibility) but isn’t hyperactive or impulsive.

2. Hyperactive-Impulsive

This type occurs when a person has symptoms of hyperactivity and impulsivity but not inattention.

3. Combined

This type is when a person has symptoms of inattention, hyperactivity, and impulsivity.


Any child can be fidgety or have trouble paying attention. But a child with ADHD has these symptoms to an extent that they can become a distraction at home or in the classroom.

The three primary symptoms are:

  • inattention
  • hyperactivity
  • impulsiveness

With each set of symptoms, there are a number of criteria that a child will need to meet in order to be diagnosed. The number of criteria needed for a diagnosis can vary by age. Children up to age 16 must show six or more symptoms. Anyone over the age of 17 only needs five.

Symptoms have to be present for at least six months and must be inappropriate for a child’s developmental level.


Inattention, or trouble focusing, is one symptom of ADHD. A child can be diagnosed as inattentive if the child:

  • is easily distracted
  • is forgetful, even in daily activities
  • fails to give close attention to details in school work or other activities, including making careless mistakes
  • has trouble keeping attention on tasks or activities
  • ignores a speaker, even when spoken to directly
  • does not follow instructions, fails to finish schoolwork or chores, and loses focus or is easily side-tracked
  • has trouble with organization
  • dislikes and avoids tasks that require long periods of mental effort, such as homework
  • loses vital things needed for tasks and activities (e.g., books, keys, wallet, phone)

Hyperactivity and Impulsivity

A child can be diagnosed as hyperactive or impulsive if the child:

  • appears to be always on the go
  • excessively talks
  • has severe difficulty waiting for their turn
  • squirms in their seat, taps their hands or feet, or fidgets
  • gets up from a seat when remaining seated is expected
  • runs around or climbs in inappropriate situations
  • is unable to quietly play or take part in leisure activities
  • blurts out an answer before a question has been finished
  • intrudes on and interrupts others constantly

More Criteria

Along with symptoms of inattention, hyperactivity, and impulsivity, a child or adult must meet the following additional criteria:

  • displays several symptoms before the age of 12
  • exhibits symptoms in more than one setting, such as school, at home, with friends, or other activities
  • shows clear evidence that the symptoms interfere with their functioning at school or work, or impact their ability to socialize with others
  • the symptoms are not explained by another condition, such as psychotic, mood, or anxiety disorders

Adult ADHD

Adults with ADHD have typically had the disorder since childhood, but it may not be diagnosed until later in life. An evaluation usually occurs at the prompting of a peer, family member, or co-worker who has observed problems at work or in relationships.

Adults can be diagnosed with any of the three subtypes of ADHD. Adult ADHD symptoms can be somewhat different from those experienced by children because of the relative maturity of adults, as well as physical differences between adults and children.


The symptoms can range from mild to severe, depending on a person’s unique physiology and environment. Some people experience mild inattentiveness or hyperactivity when they perform a task they don’t enjoy, but they have the ability to focus on tasks they like. Others may experience more severe symptoms. These can have a negative impact in school, at work, and in social situations.

Symptoms seem to be more severe in unstructured group situations (for example, on the playground) than in more structured situations where rewards are given (in the classroom). Other conditions, such as depression, anxiety, or a learning disability may worsen symptoms. Some people report that symptoms go away with age. For example, an adult with ADHD who was hyperactive as a child may find that they’re now able to remain seated or curb some impulsivity.


The good news is that you are one step closer to finding the right treatment to help you cope by determining your type of attention deficit disorder and its severity. Be sure to discuss all your symptoms with your doctor so you get an accurate diagnosis, as this is the first step to getting proper treatment.

Read the 29 Things Only a Person with ADHD Would Understand

You asked, we answered

  • Can a child “outgrow” ADHD or will it continue into adulthood if left untreated?
  • Current thinking suggests that as the child grows, the prefrontal cortex grows/matures as well, thus decreasing symptoms. It has been suggested that roughly one-third of people no longer exhibit symptoms of ADHD during adulthood. Others may continue to exhibit symptoms, but ones that are milder than those noted during childhood and adolescence.


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