Diagnosing Adolescent ADHD

Susan D. Swick, MD, and Michael S. Jellinek, MD

March 17, 2022

Pediatricians are increasingly expert in the assessment and treatment of attention-deficit/hyperactivity disorder. But what do you do when adolescents present to your office saying they think they have ADHD? While ADHD is a common and treatable disorder of youth, it is important to take special care when assessing an adolescent. Difficulties with attention and concentration are common symptoms for many different challenges of adolescence, and for ADHD to be the underlying cause, those symptoms must have started prior to adolescence (according to DSM-5, prior to the age of 12). When your adolescent patients or their parents come to your office complaining of inattention, it is important to consider the full range of possible explanations.


We have written in this column previously about the challenges that adolescents face in getting adequate sleep consistently. Teenagers, on average, need more than 9 hours of sleep nightly and American teenagers get fewer than 6. This mismatch is because of physiologic shifts that move their natural sleep onset time significantly later, while school still starts early. It's often compounded by other demands on their time, including homework, extracurricular activities, and the gravitational pull of social connections. Independent teenagers make their own decisions about how to manage their time and may feel sleep is optional, or manage their fatigue with naps and caffeine, both of which will further compromise the quality and efficiency of sleep.

Dr Susan Swick

Chronic sleep deprivation will present with difficulties with focus, attention, memory, and cognitive performance. Treatment of this problem with stimulants is likely to make the underlying poor sleep habits even worse. When your patient presents complaining of difficulty concentrating and worsening school performance, be sure to start with a thorough sleep history, and always provide guidance about the body's need for sleep and healthy sleep habits.


Anxiety disorders are the most common psychiatric illnesses of youth, with estimates of as many as 30% of children and adolescents experiencing one. The true prevalence of ADHD is estimated to be about 4% of the population. Whether social phobia, generalized anxiety disorder, or even posttraumatic stress disorder, anxiety disorders interfere with attention as ruminative worry tends to distract those experiencing it. It can also affect attention and focus indirectly by interfering with restful sleep. Anxiety disorders can be difficult to identify, as the sufferers typically internalize their symptoms. But inquire about specific worries (such as speaking in front of others, meeting new people, or an illness or accident striking themselves or a loved one) and how much time they take up. Explore if worries fill their thoughts during quiet or downtime, and explore more about their worries. You may use a screening instrument such as the Pediatric Symptom Checklist or the SCARED, both of which will indicate a likely problem with anxiety. While it is possible to have comorbid ADHD with an anxiety disorder, the anxiety disorder will likely worsen with stimulants and should be treated first. These are usually curable illnesses and you may find that remission of anxiety symptoms resolves the attentional problems.


Mood disorders are less common than anxiety disorders in youth, but far more prevalent than ADHD. And depression is usually marked by serious difficulty concentrating across settings (including for things that were previously very interesting). A sullen teenager who is deeply self-critical about school performance would benefit from exploration of associated changes in mood, interests, energy, appetite, sleep, and for feelings of worthlessness, guilt, and suicidal thoughts. The PHQ9A is a simple, free screening instrument that is reasonable to use with every sick visit (and well-check) with your adolescent patients, given the risks of undetected and untreated depression. If your patient presents complaining of poor school performance, always screen for depression. As with anxiety disorders, comorbid ADHD is possible, but it is always recommended to treat the mood disorder first and then to assess for residual ADHD symptoms once the mood disorder is in remission.

Substance Abuse

Adolescence is a time of exploration, and drug and alcohol use is common. While attentional impairment will happen with intoxication, occasional or rare use should not lead to consistent impairment in school. But when parents are more worried than their children about a significant change in school performance, it is important to screen for substance abuse. A child with a secret substance use disorder will often present with behavioral changes and deteriorating school performance and might deny any drug or alcohol use to parents. Indeed, stimulants have some street value and some patients may be seeking a stimulant prescription to sell or trade for other drugs. Regular marijuana use may present with only deteriorating school performance and no irritability or other noticeable behavioral changes. Marijuana is seen as safe and even healthy by many teenagers (and even many parents), and some youth may be using it recreationally or to manage difficulties with sleep, anxiety, or mood symptoms.

Dr Michael Jellinek

But there is compelling evidence that marijuana use causes cognitive impairment, including difficulty with sustaining attention, short-term memory, and processing speed, for as long as 24 hours after use. If a teenager is using marijuana daily after school, it is certainly going to interfere, in a dose-dependent manner, with attention and cognitive function. Sustained heavy use can lead to permanent cognitive deficits. It can also trigger or worsen anxiety or mood symptoms (contrary to much popular opinion).

Gathering a thorough substance use history is essential when assessing a teenager for difficulties with focus or attention, especially when these are accompanied by change in behavior and school performance. Remember, it is critical to interview these children without their parents present to invite them to be forthcoming with you.


While true ADHD should have been present throughout childhood, it is possible that the symptoms have become noticeable only in adolescence. For patients with very high intelligence and lower levels of impulsivity and hyperactivity, they might easily have "flown under the radar" during their elementary and even middle school years. Their difficulties with attention and focus might become apparent only when the volume and difficulty of schoolwork both are great enough that their intelligence is not enough to get good grades. That is, their problems with executive function, prioritizing, shifting sets, and completing tasks in a timely way make it impossible to keep up good grades when the work gets harder.

Your history should reveal a long history of dreaminess or distractibility, a tendency to lose and forget things, and the other symptoms of inattention. Did they often seem to not be listening when they were younger? Forget to hand in homework? Leave chores unfinished? Leave messes behind everywhere they went? These will not be definitive, but they do reassure that symptoms may have been present for a long time, even if school performance was considered fine until the workload got too large. If such problems were not present before puberty, consider whether a subtle learning disability could be impairing them as they face more challenging academic subjects.

If you have ruled out anxiety, mood, and substance use concerns, and helped them to address a sleep deficit, then you can proceed. It is worthwhile to get Vanderbilt Assessments as you would for a younger child. If they meet criteria, discuss the risks and benefits of medication, executive skills coaching, and environmental adjustments (extra time for tests, a less stimulating environment) that can help them explore academic challenges without the discouragement that ADHD can bring.

Swick is physician in chief at Ohana, Center for Child and Adolescent Behavioral Health, Community Hospital of the Monterey (Calif.) Peninsula. Jellinek is professor emeritus of psychiatry and pediatrics, Harvard Medical School, Boston. Email them at

This article originally appeared on, part of the Medscape Professional Network.


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