Athletes With Attention-Deficit/Hyperactivity Disorder: Position Statement of the American Medical Society for Sports Medicine

Abstract

Athletes of all ages may be affected by medical and mental health issues. Sports medicine physicians should be familiar with common conditions that may affect the well-being of athletes, such as attention-deficit/hyperactivity disorder (ADHD). ADHD behaviors have the potential to affect a person's ability to concentrate. It is likely that social and cognitive therapies combined with pharmacotherapy will be the most effective way to treat ADHD in athletes. Medications used for ADHD, especially stimulant types, are known to improve alertness, reaction time, anaerobic performance, and endurance, which would potentially improve athletic performance. Furthermore, stimulant medications may enable student athletes with ADHD to focus on academic studies for longer periods of time, beyond usual levels of fatigue, important for those who may be exhausted after practices and games. The purported performance enhancement effects and potential adverse effects of stimulant medications have prompted many sports governing bodies to ban prescription stimulants or establish strict rules for their use. Athletes taking physician-prescribed stimulants to treat ADHD need to provide the appropriate documentation for approval before competition or risk punitive measures. Physicians should strive to provide a high quality of care to athletes with ADHD through early diagnosis, appropriate and careful multidisciplinary treatment, and complete and timely documentation to facilitate continued sports participation.

INTRODUCTION

Attention-deficit/hyperactivity disorder (ADHD) is a relatively common neurobehavioral disorder, affecting up to 11% of the population worldwide.^1–5 ADHD is more common among men than women⁶ and is presumed to be more prevalent among athletes.^1,2,5 Diagnosis of ADHD remains largely subjective; an evidence-based, standardized diagnostic tool should be used. Management strategies for ADHD are multifaceted, ranging from behavioral therapy to pharmacologic management and physical activity.^1–5,7–10 Prescribing physicians should be vigilant for potential unfair performance advantages because of stimulant use, differentiating these from changes in performance because of appropriate treatment of ADHD. It is noteworthy that ADHD treatment may have unique direct and indirect impacts on an athlete's performance. In addition, the risks of unfair performance advantages from using stimulants and their adverse effects, especially regarding heat-related illnesses, must be deliberated.¹¹

The primary purpose of this position statement is to evaluate current evidence on the proper diagnosis and management of ADHD among athletes at different competition levels, providing guidance for sports medicine practitioners that leverages scientific evidence for clinical utility. This study updates and expands on the 2011 American Medical Society for Sports Medicine (AMSSM) position statement.¹²

METHODOLOGY

Writing Team Selection Process

A call for a lead author was sent to all AMSSM members; although AMSSM has an international reach, its activities are focused mainly within the US. The lead author was chosen by the AMSSM Board of Directors, at which time a separate call for coauthors was sent. The AMSSM Board of Directors and the lead author reviewed responses. Coauthors were chosen with the goal of a writing team that represented the diverse membership of AMSSM, including sex, clinical specialty, focus of expertise, geographic region, and race and ethnicity.

American Medical Society for Sports Medicine is a multidisciplinary organization of sports medicine physicians dedicated to education, research, advocacy, and care of athletes of all ages. Most AMSSM members are board-certified primary care physicians with fellowship training in sports medicine who combine their practice of sports medicine with their primary specialty. AMSSM includes members who specialize solely in nonsurgical sports medicine and serve as team physicians at the youth level, secondary schools, National Collegiate Athletic Association (NCAA), National Football League, Major League Baseball, National Basketball Association, Women's National Basketball Association, Major League Soccer, and National Hockey League, and with Olympic and Paralympic teams. By nature of their training and experience, sports medicine physicians are ideally suited to provide comprehensive medical care for athletes, sports teams, or active individuals looking to maintain a healthy lifestyle.

METHODS

Studies were identified by a health sciences librarian by developing and running searches in the following databases: MEDLINE (1946-Present), Embase (1974-Present), Cochrane Central Register of Controlled Trials (1991-Present), and Cochrane Database of Systematic Reviews (2005-Present) via the Ovid interface, and Science Citation Index Expanded (1975-Present) and Emerging Sources Citation Index (2015-Present) via the Web of Science interface. There were no limits to language or publication dates, a strength of this review. Filters to remove editorials, letters, conference posters, and proceedings were included, and filters to remove animal studies, a possible limitation. Search strategies were created using a combination of keywords and standardized index terms. Search terms included standard NLM Medical Subject Headings and Emtree terms, and keywords, such as “attention deficit disorder with hyperactivity,” “ADHD,” “athletes,” “sports,” and concepts for each specific aim. The search strategy for all specific aims was completed between September 20, 2021, and October 18, 2021, resulting in 8142 unique articles. Full search strategies are available on request.

Specific aims of the article were developed through periodic meetings. The writing team was divided into subgroups (Table 1). Consensus on article inclusion and draft content was reached within each subgroup before the full group content meeting. This article is not a primer on ADHD diagnosis and treatment, but rather focuses on issues most pertinent to the competitive athlete with ADHD.

TABLE 1. - Division of Work for Members of the Writing Team by Section

Section	Author(s)
Abstract	Pujalte
Introduction	Khodaee, Pujalte
Methodology	Brigham,* Clifton*
Results/Literature summary
Diagnosis and management of ADHD	Pujalte
ADHD mimics: Pattern identification for differentiation	Narducci
ADHD and issues related to diversity, equity, and inclusivity	Callender, King, Pujalte, Wolf
Pharmacotherapy	King, Liebman
Medication adverse effects	Liebman, Smith
The role of exercise in the treatment of ADHD	Callender, Nuti
Effects of ADHD on sports participation	Kane, Liebman, Logan
Effects of ADHD medications on athletic performance	Narducci, Smith
The relationship between ADHD and concussions	Wolf
Regulatory issues	Israel, King
References	Brigham,* Clifton*

^*Acknowledged contributor.

RESULTS/LITERATURE SUMMARY

Diagnosis and Management of ADHD

Diagnosing ADHD principally warrants comprehensive input (eg, interviews or assessment tools) from the patient and their parents, caregivers, and teachers. Other conditions that resemble ADHD (eg, depression, anxiety, posttraumatic stress disorder) should be assessed through diagnostic evaluation. Table 2 presents diagnostic criteria recommended by the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition.¹³ Neuroimaging and laboratory evaluation are rarely necessary to diagnose ADHD, especially when no other etiologies are being considered.¹⁴

TABLE 2. - DSM-V Criteria for the Diagnosis of ADHD

Persistent Pattern of Inattention And/Or Hyperactivity-Impulsivity that Interferes with Functioning or Development
Inattention
Six or more symptoms of inattention in children up to 16 years old, or 5 or more in adolescents aged 17 years or older and adults. Symptoms have been present for at least 6 months and are inappropriate for the person's developmental level: • Often fails to give close attention to details or makes careless mistakes in schoolwork, at work, or with other activities • Often has trouble holding attention to tasks or play activities • Often does not seem to listen when spoken to directly • Often does not follow through on instructions and fails to finish schoolwork, chores, or duties in the workplace (eg, loses focus, is sidetracked) • Often has trouble organizing tasks and activities • Often avoids, dislikes, or is reluctant to do tasks that require mental effort over a long period of time (such as schoolwork or homework) • Often loses things necessary for tasks and activities (eg, school materials, pencils, books, tools, wallets, keys, paperwork, eyeglasses, or mobile telephones) • Is often easily distracted • Often forgetful in daily activities
Hyperactivity-impulsivity
Six or more symptoms of hyperactivity-impulsivity in children up to 16 years old, or 5 or more in adolescents aged 17 years or older and adults. Symptoms of hyperactivity-impulsivity have been present for at least 6 months to an extent that is disruptive and inappropriate for the person's developmental level: • often fidgets with or taps hands or feet, or squirms in seat • Often leaves a seat in situations where remaining seated is expected • Often runs about or climbs in situations where it is not appropriate (adolescents or adults may be limited to feeling restless) • Often unable to play or take part quietly in leisure activities • Is often “on the go” or acting as if “driven by a motor” • Often talks excessively • Often blurts out an answer before a question has been completed • Often has trouble waiting for their turn • Often interrupts or intrudes on others (eg, “butts into” conversations or games)
The following conditions must also be met:
• Several inattentive or hyperactive-impulsive symptoms present before 12 years old • Several symptoms present in 2 or more settings (eg, at home, school, or work; with friends or relatives; in other activities) • Clear evidence that symptoms interfere with or reduce the quality of social, school, or work functioning • Symptoms not better explained by another mental disorder (eg, mood disorder, anxiety disorder, dissociative disorder, or personality disorder)  • Symptoms do not happen only during the course of schizophrenia or other psychotic disorder

Abbreviations: ADHD, attention-deficit/hyperactivity disorder; DSM-V, diagnostic and statistical manual of mental disorders, Fifth Edition.

A team approach that includes the athlete is preferred.^1,3,4 The primary members of this team (ie, health care professionals, athlete, family members) need to participate in discussions about short- and long-term treatment plans along with coping and management strategies. Teachers who work closely with athletes should also be incorporated into the intervention and management team.

Cognitive behavioral therapy and social skills training alone are not sufficient for ADHD management.¹⁵ The most effective treatment for ADHD is a multidisciplinary approach that combines pharmacotherapy with cognitive and social therapies. Left untreated, ADHD can negatively impact performance in school, job stability,¹⁶ self-esteem,¹⁷ relationships, substance use disorder,⁶ and mood (eg, anxiety).¹⁸

Of the various medication options (Table 3), stimulants are considered the first-line treatment with selected nonstimulants prescribed less frequently.¹⁹ Family and personal histories of cardiovascular diseases should be examined before prescribing stimulant medications for ADHD.²⁰

TABLE 3. - Commonly Used Medications for ADHD and Known Pharmacology

Medication	Pharmacology
Stimulants
Methylphenidate	Increases norepinephrine and dopamine release and prevents reuptake
Dextroamphetamine-amphetamine salts	Increases norepinephrine and dopamine release and prevents reuptake
Dextroamphetamine	Increases norepinephrine and dopamine release and prevents reuptake
Modafinil	Inhibits GABA release, possible α1 agonist
Nonstimulants
Atomoxetine	Norepinephrine reuptake inhibitor
Bupropion*	Norepinephrine and dopamine reuptake inhibitor
Guanfacine	Selective α2A agonist
Tricyclic antidepressants*
Amitriptyline	Norepinephrine and dopamine reuptake inhibitor Norepinephrine and dopamine reuptake inhibitor Norepinephrine and dopamine reuptake inhibitor Norepinephrine and dopamine reuptake inhibitor
Desipramine
Imipramine
Nortriptyline

Abbreviations: ADHD, attention-deficit/hyperactivity disorder; GABA, γ-aminobutyric acid.

^*Off-label.

It is essential to educate coaches, families, and other sports personnel working with athletes with ADHD about this disorder. Privacy of the patient should be maintained throughout these interactions. The patient and their parents (if applicable) need to document their approval to involve other individuals. The extent of the team's involvement should be detailed in the medical record by the physician when appropriate.

ADHD Mimics: Pattern Identification for Differentiation

There are various medical conditions that can mimic the signs and symptoms of ADHD. Appropriate diagnosis and treatment of ADHD is paramount, particularly in athletes, because there are potential adverse effects of pharmacologic treatment and restrictions placed by various sports organizations regarding the use of stimulant medications.²¹

Difficulty concentrating, inattentiveness, and impulsivity can be presenting symptoms of several other psychological conditions, including, but not limited to major depressive disorder, generalized anxiety disorder, posttraumatic stress disorder, bipolar disorder, and obsessive-compulsive disorder.²² ADHD symptoms are often instigated by external stimuli and are constant, whereas symptoms of mood disorder are more commonly episodic.²³ Use of condition-specific screening tools, such as Patient Health Questionnaire-9 and Generalized Anxiety Disorder 7-item scale, can help differentiate between ADHD and other psychologic disorders, although the diagnoses are not mutually exclusive (Table 4).

TABLE 4. - Psychological Conditions that May Lead to ADHD-like Symptomatology, and Corresponding Assessments

Conditions	Assessment Tools
Learning disabilities
Intellectual disability	Intelligence quotient tests • Cognitive assessment system • Kaufman assessment battery for children • Stanford–Binet intelligence scale • Wechsler adult/Children intelligence scale
Language communication disorders	Sequenced inventory communication development
Autism spectrum disorders	Modified checklist for autism in Toddlers (18 and 24 months) Child development review (18-60 months) Pervasive developmental disorders screening Autism screening questionnaire Eyberg Child behavior inventory
Depression disorder	Children • Children's depression inventory • Reynolds Child depression scale Adolescents • Reynolds adolescent depression scale • CES-D • BDI • PHQ-9 Adults • CES-D • BDI • PHQ-9
Anxiety disorder	Generalized anxiety disorder scale Short health anxiety inventory Beck anxiety scale
Attachment disorders
Oppositional defiant disorder	Freely available scales • National institute for Children's health quality Vanderbilt assessment scale • Swanson, Nolan and pelham, version IV, teacher and parent rating scale Fee for use • Connors 3 • Child behavior checklist
Obsessive compulsive disorder	Obsessive-compulsive inventory-revised Florida obsessive-compulsive inventory For monitoring • Yale–Brown obsessive-compulsive scale
PTSD	PTSD screening checklist Startle, physiologic arousal, anger, numb score
Personality disorder
Substance abuse	CAGEa questions National institute on alcohol abuse and alcoholism quantity and frequency questionnaire Drug abuse screening test United States preventive services task force–recommended screening tools • AUDIT • AUDIT-C

Abbreviations: ADHD, attention-deficit/hyperactivity disorder; AUDIT, alcohol use disorders identification test; BDI, beck depression inventory; CES-D, center for epidemiologic studies depression scale; PHQ-9, Patient Health Questionnaire-9; PTSD, posttraumatic stress disorder.

Acronym: Cutting down; Annoyed by criticism, Guilty feeling, Eye-opener.

Behavioral dysfunction and outbursts are common among populations with autism spectrum disorders, oppositional defiant disorder, some personality disorders, substance use or abuse, and ADHD.^22,24 Persons with autism spectrum disorders often exhibit an inability to tolerate alterations in their environment, whereas features of impaired behavioral composure are more common in ADHD.^25,26

Medical conditions, such as lead poisoning,^27,28 malnutrition-related deficiencies,²⁹ cardiovascular pathologies,^20,30 sleep disorders,^31,32 and endocrine disorders³³ can be distinguished from ADHD through history, physical examination, and other distinctive tests (Table 5).

TABLE 5. - Physiological Conditions Mimicking or to Be Considered as Differential Diagnosis for ADHD

Conditions	Examples	Additional Information and Further Testing
Neurodevelopmental syndromes	Fragile X syndrome, fetal alcohol syndrome	Genetic testing
Motor coordination disorders	Cerebral palsy, muscular dystrophies	Genetic testing, muscle biopsy
Hearing or visual impairment	Congenital versus acquired causes	Vestibular/vision testing, audiometry; referral to ophthalmologist, neuro-ophthalmologist, audiologist, or otorhinolaryngologist
Central nervous system conditions (infectious, trauma)	Encephalitis, meningitis, neurosyphilis, CVA, sickle cell CVA, traumatic brain injury, concussion	Brain imaging: MRI, magnetic resonance angiography, functional MRI, quantitative EEG Cerebrospinal fluid testing
Iron deficiency with or without anemia	Chronic blood loss, decreased production or dietary intake, chronic kidney disease, malabsorption	Complete blood count, iron studies
Seizure disorder	Epilepsy, absence or myoclonic seizures	EEG, referral to neurology
Lead poisoning		Measure blood levels
Endocrine disorders	Thyroid disease, hyper/hypothyroidism, thyrotoxicosis, diabetes mellitus, exogenous ingestion of insulin	Thyroid studies, hemoglobin A1c, insulin, C-peptide level
Cardiac abnormalities	Heart failure	Electrocardiography, echocardiography, cardiology referral
Malnourishment	Malabsorptive disorders (celiac disease, inflammatory bowel disease), eating disorders, low energy availability Vitamin deficiency	Assess growth parameters Dual-energy X-ray absorptiometry, eating disorder screening questionnaires, laboratory testing (prealbumin, leptin, erythrocyte sedimentation rate)
Sleep disorders	Sleep apnea, narcolepsy, restless leg syndrome, parasomnias	Polysomnography, ferritin levels

Abbreviations: ADHD, attention-deficit/hyperactivity disorder; CVA, cerebrovascular accident; EEG, electroencephalography; MRI, magnetic resonance imaging.

Central nervous system trauma or infection can mimic ADHD. Similar to ADHD, sports-related injuries, such as concussions, can lead to mood disturbances, cognitive dysfunction, reduced attention, and somatic idiosyncrasies.^3,34,35 History of multiple head injuries, central nervous system infection, cerebral vascular disease, or brain tumor suggests a diagnosis other than ADHD.^36,37

Conditions affecting the vestibular-visual system simulate ADHD symptoms and can be assessed with vestibular, visual, and audiologic testing and referral to suitable specialists (ie, audiologist, ophthalmologist, or otorhinolaryngologist).^38,39

It has also been reported that psychosocial factors, such as social media, can lead to impaired attention, memory, information processing, and problem-solving (Table 6).^40,41 Effects of stress or considerable fluctuations in the athlete's environment, including school absence, disorientation, and changes in mental health, can mimic ADHD.⁴² Moreover, the dynamics of caregiver relationships, specifically inadequate or corrective parenting and parental psychopathology, may result in childhood ADHD-like behaviors that can persist into adulthood.^43–45

TABLE 6. - Psychosocial/Environmental Scenarios that May Lead to ADHD-like Symptomatology, and Corresponding Testing

Condition	Examples	Additional Methods of Testing
Stress or distraction by external stimuli	Occurring in multiple environments (eg, school, home, work, social media)	• Vanderbilt ADHD diagnostic teacher and parent rating scales, Brown attention-deficit disorder symptom assessment scale, Conners abbreviated symptom questionnaire • HEADSS psychosocial interview
Caregiver dynamics	Inadequate or corrective parenting Parental psychopathology (eg, substance abuse, psychological disorder)	• Mental health assessment of caregivers • Child protective services involvement
Child abuse or neglect		• Skeletal survey radiography, head imaging • Abdominal trauma: Liver function tests, lipase/amylase, urinalysis, fecal occult blood test • Coagulation studies: Complete blood count, platelets, prothrombin time, partial thromboplastin time • Urine toxicology
Adverse childhood experiences

Abbreviations: ADHD, attention-deficit/hyperactivity disorder; HEADSS, home, education/employment, peer group activities, drugs, sexuality, suicide/depression.

Attention-deficit/hyperactivity disorder is a complex issue that may be too challenging for a single health care professional to manage. As ADHD can imitate or coincide with other diagnoses, understanding these parallels and distinguishing them from ADHD will promote appropriate diagnosis and management of athletes with ADHD. We are advocating a team approach that is comprised of clinicians with specific expertise for adequate clinical management (Tables 4–6).

ADHD and Issues Related to Diversity, Equity, and Inclusivity

Globally, ADHD is more prevalent in boys than girls.⁴⁶ However, diagnosis of ADHD in girls is often delayed. Social norms for behavior among girls may disguise ADHD-related dysfunction and delay observation of ADHD symptoms.

Boys are more likely to be referred for hyperactive symptoms, whereas girls are more likely to be referred for learning problems.⁴⁷ This might affect the treatment rates for ADHD.⁴⁸ Because of the frequency of disruptive classroom behavior, boys are often presumed to exhibit gender-correlated behavioral patterns compared with girls. However, girls tend to have their ADHD behaviors overlooked and are diagnosed with generalized anxiety disorder.⁴⁹ When expulsion and suspension are a school's primary means of handling behavioral problems, boys are more likely to have ADHD behaviors misinterpreted as conduct issues.⁵⁰ In contrast, although girls receive school suspension less often, this does not mean that girls with ADHD are not impaired and do not need referral for treatment.⁵¹

More research is warranted to examine the contributing risk factors for ADHD and the components of socioeconomic status.⁵² Compliance with medications and other treatments correlate well with the socioeconomic background of the child's family. When receiving behavioral and pharmacologic treatments, children from low socioeconomic backgrounds do not experience substantial improvement and are less likely to adhere to treatment.⁵³ Parental engagement may be the primary determinant, making it even more important that clinicians actively address cultural competencies to aid in communication with families about their child's ADHD treatment.^54,55

Children from marginalized communities are less likely to receive an ADHD diagnosis than the most represented groups.⁵⁶ Black people are about two-thirds less likely to be recognized as having ADHD than White people. In one study, Black children were diagnosed with ADHD less often than White children despite more symptoms of distractibility and hyperactivity.⁵⁷ Children of marginalized communities diagnosed with ADHD are less likely to use their prescribed medication and have a higher drop-out rate from treatment. There are different hypotheses explaining these disparities: 1) less health care access for those in marginalized communities; 2) poor ability to pay for health care; 3) communication and language barriers; and 4) known ADHD stigma and negative views toward disability.⁵⁸

Children and adolescents with parents born in traditionally non–English-speaking countries are less likely to be treated with stimulants.⁵⁹ For immigrant children, ADHD medication is prescribed less frequently, and the children are less likely to take the medication. This increases with the concentration of foreign-born children in the geographic area around the child's home.⁶⁰

The COVID-19 pandemic has likely led to specific risks for individuals with ADHD, especially those who are vulnerable to distress caused by physical distancing measures. Loss of social structure because of school closures, distance from hobbies and friends, and anxiety related to isolation may cause behavioral disruptions in children and adolescents with ADHD, in addition to worsening their sleep issues. Preexisting disparities because of factors discussed above may have worsened during the COVID-19 pandemic. More research is required to analyze the pandemic's impact in this regard.⁶¹

Pharmacotherapy

Each drug has its own special considerations when used by athletes. Table 3 lists medications currently approved by the US Food and Drug Association (FDA) for ADHD. Medications used to treat ADHD are categorized as stimulants or nonstimulants; most published research addresses norepinephrine and dopamine pathways.^62,63 Stimulants remain first-line medications; nonstimulant medications may be considered when stimulants fail, are poorly tolerated, or are contraindicated.^64,65 Stimulants for ADHD treatment include methylphenidate, dextroamphetamine-amphetamine salts, modafinil, and dextroamphetamine; most are available in short- and long-acting formulations.^66,67 Nonstimulant medications include atomoxetine, tricyclic antidepressants (TCAs), clonidine, guanfacine, and viloxazine.^1,12,68,69 Adverse effects of TCAs may make them less tolerable to athletes. Bupropion is prescribed for off-label use and is typically an adjunct to first-line therapy.^12,70,71

Medication Adverse Effects

Medication class and mechanism of action often determine the adverse effects observed in athletes treated for ADHD.¹ When discussing possible adverse effects, it is important to understand the mechanism of action of each drug class. Common adverse effects of any stimulant include decreased appetite, gastrointestinal upset, sleep disturbances, irritability, headache, elevated heart rate, and increased blood pressure.^2,5,11,66,70

Sudden cardiac death in athletes is a concern and has been reported in those using stimulants to manage their ADHD.^3,11 It is currently believed that stimulant use does not increase the risk of sudden cardiac death in patients without underlying cardiovascular disease.^1,3,11,72 However, dextroamphetamine-amphetamine salts carry a warning for cardiovascular events and sudden death with misuse. Therefore, stimulants should not be prescribed for athletes at risk for cardiovascular disease. Current evidence does not support ordering electrocardiography routinely because of starting stimulant medications in children.^73–75 Although stimulant medications may cause elevations in heart rate and blood pressure, there seems to be no increased incidence of sudden cardiac death with the judicious, proper use of stimulant medications for the treatment of ADHD.^76,77 Routinely ordering electrocardiography before initiating stimulant medications has not been shown to add benefit in preventing sudden cardiac events^78,79 and may result in treatment delay and increased or unnecessary anxiety. Detailed family history and physical examination are therefore crucial before initiation of stimulants, because these will be the main determinants of whether electrocardiography is needed. All children started on stimulant medications for ADHD should be monitored for palpitations, chest pain, high blood pressure, and tachycardia.^80,81 Clinicians must also remember that stimulants can theoretically increase the risk of arrhythmias.⁸²

Athletes taking stimulants have an elevated core body temperature with physical activity that can increase the risk of exertional heat illness.⁸³ In athletes whose sports require considerable exertion or occur in hot or humid environments, clinicians must understand this increased risk of heat illness when prescribing stimulants for ADHD. Of note, clinically relevant hyperthermia, rhabdomyolysis, and hypertension after therapeutic use of stimulants for ADHD has not been reported.^84–86 Risk for these effects is theoretical and extrapolated from data on use of ephedra as a performance enhancer and improper stimulant use or abuse.^86–88 More studies are needed to observe whether proper use of stimulant medications in athletes with ADHD can lead to such adverse effects. Based on current evidence, it is likely that properly dosed stimulants can be safely used without clinically significant risk.^89,90 Treatment need not be delayed, because benefits can outweigh the theoretical risks as long as monitoring begins with the initial prescription of the stimulant.

Atomoxetine is one of the most commonly prescribed nonstimulant medications for ADHD.⁵ Its adverse effects include gastrointestinal disturbance, weight gain, liver toxicity, and hypertensive crisis.^1,3,91 Clonidine and guanfacine, both α₂ agonists, are also nonstimulant options with common adverse effects of dizziness, sedation, bradycardia, hypotension, and QT prolongation.^1,3 TCAs are another off-label option, but the potential adverse effects (eg, weight gain, dry mouth, fatigue, cardiac dysrhythmia) often prevent their use in athletes.³ Of note, suicidal tendency is among the top 20 reported adverse effects of nonstimulant medications.⁹¹ Suicidal ideation and mania are serious potential adverse effects of viloxazine; less serious adverse effects include elevated blood pressure and heart rate, headache, and fatigue.⁹²

The Role of Exercise in the Treatment of ADHD

Despite being the most commonly diagnosed pediatric psychiatric disorder,⁹³ the prevalence of ADHD may be disproportionately represented in athletes because of the attention-activating effects of physical activity.^{3,11,12,14,94–98} Athletes, families, and caregivers who are apprehensive about the mainstream treatment with psychostimulant medications may seek exercise as an alternative therapeutic option.^3,11,93 Sports participation may help develop physical skills and control in young athletes with ADHD by building motor coordination and static-dynamic balance and improving their psychosocial skills. More research is needed to demonstrate whether the prevalence of ADHD is overrepresented in athletes because of attention-activating effects of physical activity, or because those with ADHD gravitate toward pursuits that require attention activation.

Athletic participation and regular exercise serve as emotional and physical outlets and offer positive reinforcement in a venue where impulsivity can be an advantage.^11,95,96,99 Evidence suggests that intense exercise is beneficial for major symptoms observed in children with ADHD (ie, lack of attention, hyperactivity, and impulsive behaviors).⁹³ Although only a minimum volume of exercise is needed to attain meaningful symptom improvement, physical activity past the minimum may further improve symptoms.¹⁰⁰ More studies are needed to determine whether a ceiling effect exists with exercise in this regard.

Research suggests that exercise positively affects ADHD symptoms without adverse events.⁹ Chuang et al¹⁰¹ found that 30 minutes of continuous moderate aerobic exercise resulted in significantly improved reaction time in a cognitive task suggesting improvement in attention. Medina and colleagues¹⁰² reported that 30 minutes of intermittent exercise (2 minutes work to 1 minute recovery) improved response times, stabilized impulsivity, and increased attention. There is also evidence that exercise enhances the effects of medications.¹⁰³

Moderate-to-intense aerobic activity and varied sport tasks are independently effective in mitigating cognitive, behavioral, and physical symptoms of ADHD.⁷⁰ Immediate single-exercise tasks and repeated regular exercise positively affect symptoms of ADHD over time, specifically inattention and impulsivity. Therefore, exercise should be a regular component of a treatment strategy for those with ADHD, and programs should be designed to provide opportunities that combine cognitive training and behavioral education.¹⁰⁰ Although more research is needed, current findings suggest that exercise programs are helpful for behavior problems and obesity⁹ and, therefore, should be recommended as adjuncts to ADHD management. Children with ADHD are themselves at increased risk for becoming physically inactive and obese. Physical activity, which reduces the risk for inattention symptoms later in adolescence, can be recommended as a unique approach to treating ADHD.¹⁰⁴

Effects of ADHD on Sports Participation

It is uncertain whether ADHD has a direct effect on participation in organized sports. Gross motor skills are frequently impaired in patients with ADHD, which could hinder participation in sports and lead to reduced social interaction.^105,106 Stimulant use during exercise can lead to higher core temperatures and heart rates without an awareness of increased effort.^83,107,108 Research also shows that patients with ADHD perform poorly and less efficiently in motor regulation than their neurotypical peers.¹⁰⁹ Gait abnormalities resulting from attempts to improve the base of support, such as exaggerated out-toeing and increased step rate,¹¹⁰ could certainly influence comfort and performance in an athletic setting. Children with ADHD are more likely to have low levels of physical literacy, which may affect physical performance.¹¹¹ However, more research is needed to determine how low physical literacy directly affects attention and impulsivity. Lack of a cohesive understanding of what, if any, influence an ADHD diagnosis has on sport participation rates presents a worthwhile investigative opportunity.

Effects of ADHD Medications on Athletic Performance

Athletes with ADHD may favor stimulant medication use because of perceived competitive benefits despite potential adverse effects.^112,113 Improvements in concentration and attention with stimulant use are assumed to occur because of the activation of dopaminergic and noradrenergic systems.^5,21,35,96 However, stimulation of these systems can also lead to tachycardia, hypertension, increased heart rate and blood pressure, stroke, myocardial infarction, loss of appetite, gastrointestinal impairments, rhabdomyolysis, headache, tremor, nausea, agitation, psychosis, and changes in sleep patterns,^114–117 all of which can negatively affect athletic performance. Studies have shown that methylphenidate has fewer motor and systemic effects and more cognitive actions compared with amphetamines.³⁵ The dosage, timing, duration, and type of stimulant medications can be adjusted to decrease the probable adverse effects.

The potential effects of improved endurance, anaerobic performance, reaction time, and alertness and reduced feelings of exercise fatigue with stimulants have led to their use as a performance-enhancing substance by athletes.^3,118 Even if stimulant cessation is required before competition, its use may still be beneficial to athletes outside of competition by enhancing training outcomes.^3,116 Use of stimulant medications as appetite suppressants is also appealing to some athletes who participate in weight-restricted (eg, boxing, wrestling and other combative sports, lightweight rowing) or aesthetics sports (eg, diving, figure skating, dance, cheerleading) given the assumption of improved performance with weight loss.^119,120 Although studies have shown an improvement in variables associated with success in sport (eg, acceleration, anaerobic capacity, strength, time to exhaustion, reaction time),^101,121 evidence suggesting competitive performance benefits through stimulant use in athletes is limited by sample size, dosage, novelty, consistency, and study design.^5,122,123 Unfortunately, many conclusions have been based on subjective reports, hypothetical extrapolations, limited research designs, and other nonvalidated protocols. Furthermore, studies assessing performance effects may be biased in that most were not conducted exclusively on an athletic population confirmed to have ADHD.^124,125

Theoretically, improvements in working memory, motor performance, attentiveness, judgment, and obedient behavior observed in athletes treated for ADHD offer an advantage in sport performance through enhanced coachability and focus on training and competition.^5,21,126 For some sports positions, inattention may be particularly difficult or problematic (eg, baseball outfielder), whereas in other sports positions, impulsivity may be beneficial (eg, point guard). Presumably, treating ADHD in diagnosed athletes allows for equalization of performance compared with athletes without ADHD. Clinicians must examine the influence that the symptoms of untreated ADHD can have on performance. Although untreated ADHD in athletes may impair performance because of reduced concentration, oppositional behavior, impaired self-esteem, and labile mood, it is also possible that the unstructured or impulsive behavior of untreated athletes with ADHD may lead to advantages with their athletic performance. There is inadequate research on the performance effects of ADHD medications in the athletic population; additional quality investigations are needed to confirm performance-enhancement claims.^124,127

Off-label nonpharmacologic treatment for ADHD, besides lifestyle modifications, focuses on caffeine and supplements with a high ratio of omega-3 fatty acids and eicosapentaenoic acid (EPA) to docosahexaenoic acid. Omega-3 supplementation is often discussed as a complementary intervention for ADHD with studies showing improvement when baseline EPA levels are low.^96,128 Evidence suggests potential performance advantages with caffeine and EPA supplements because of reduction in delayed-onset muscle soreness and maintenance of muscle function after eccentric exercise-induced muscle damage.^129–131 It is unknown whether such results occur in those with ADHD. There is a growing trend toward the use of caffeinated beverages to improve cognitive performance among individuals with ADHD with recent studies suggesting benefits when used as an adjuvant therapy to stimulants.¹³²

Frequently prescribed nonstimulant ADHD medications include bupropion (norepinephrine and dopamine reuptake inhibitor), atomoxetine (serotonin-norepinephrine reuptake inhibitor), and α₂ agonists clonidine and guanfacine, in extended-release formulas.^{5,116,133,134} The results of smaller trials suggest that bupropion use may decrease perceived exertion and thermal increase during exercise, thereby elevating athletes' thresholds for exercise cessation.^135,136 Atomoxetine is an FDA-approved drug for ADHD treatment in children and adults. Clonidine and guanfacine are approved for use in the pediatric population, whereas bupropion and TCAs are not FDA-approved but can still be used.¹³⁷

The Relationship Between ADHD and Concussions

Risk, Incidence, and Prevalence

Review of the literature for concussion prevalence by age, sex, and diagnosis of ADHD revealed some interesting trends. For example, the overall frequency of at least one diagnosed concussion is lowest in elementary school children without ADHD (3.2%) versus those with ADHD (7.2%).¹³⁸ About 11% of middle school children without ADHD report at least one concussion, whereas 24% of their classmates with ADHD have experienced one or more concussions.¹³⁹ In high school, 17% of students report at least one concussion, whereas 24% to 25% of those with ADHD report one or more concussions.^140,141 Just over 22% of college-age students without ADHD report a history of at least one concussion, whereas 35.2% of those with ADHD report having suffered one or more concussions.¹⁴² At younger ages, children with ADHD are about twice as likely to have suffered at least one concussion over their neurotypical peers.^138,139 In adolescent to college-age individuals, those with ADHD are about 1.6 times more likely to report at least 1 concussion.^140,141,142 In general, concussion frequency is higher in boys than girls with differences ranging from 0.4%138% to 5.5%141 for those with ADHD and from 1.0%142% to 6.4%141 for those without ADHD.

Symptom Load and Duration

There are mixed data on the interaction between ADHD and concussion duration. Older studies reported that ADHD does not affect clinical outcomes after concussion, including prolonged recovery time (>1 month).¹⁴³ More recent data, however, suggests that ADHD may affect clinical outcomes for specific populations. For example, children and adolescents with ADHD have longer recovery times for return to school and physical activity after concussion compared with youth without ADHD.^144,145 In contrast, older collegiate athletes with ADHD do not seem to have longer recovery times compared with their peers without ADHD.¹⁴⁶ Still other studies have found that older age, female sex, and the presence of an internalizing disorder (eg, depression, dysthymia, bipolar disorder) are predictors of worse outcomes after concussion for people with ADHD.¹⁴⁷ Overall, there is no clear consensus on how age affects concussion duration for patients with ADHD.

Patients with ADHD who sustain concussions experience higher concussion symptom load, in severity and number of symptoms, compared with their unaffected peers.^{143,145,148,149} This is likely because ADHD symptoms mimic concussion symptoms even in the absence of injury.¹⁵⁰ High school and collegiate athletes with ADHD are known to have higher rates of concussion-like symptoms on their preconcussion baseline assessments and return-to-play initiation assessments.^{143,151–153} Furthermore, ADHD is associated with worsened vestibular and oculomotor dysfunction and increased visual symptoms, at baseline and after concussions.^149,154,155 Neurocognitive measures, including the Immediate Post-concussion Assessment and Cognitive Test (UPMC) and other postconcussion evaluations, indicate greater impairment in those with ADHD.^{138,143,149,151,152,155–159} Notably, neurocognitive testing for school-age children with ADHD is more likely to be invalid when performed in a group setting.¹⁵³

Impact of Stimulant Medications

Young athletes with ADHD who take stimulants have a lower incidence of concussion when compared with their peers without ADHD and those with ADHD not taking stimulants.¹⁶⁰ This protective effect is theoretically because of lower impulsivity and improved executive functioning. Research examining how stimulant medications affect neurocognitive impairment on postconcussion testing has yielded mixed results with some studies saying stimulants improve test performance,^158,161,162 whereas others report no effect or mixed results.^163,164 Similarly, stimulant medications may have no effect or may shorten concussion recovery time,^145,146 but whether this is because of some physiologic mechanism or symptom masking is difficult to discern.^35,160 The effects of stimulants on athletes require periodic evaluations, including after concussions. The individualized decision regarding continuation or dosage changes needs to be made after such evaluations and may reflect, as with most medications, changes in efficacy or worsening adverse effects noted in each clinic visit.

Regulatory Issues

Stimulant medications have the potential to operate not only as ergogenic aids, potentially benefiting any athlete, but also as appetite suppressants, beneficial to athletes participating in sports with restrictive weight classifications, such as wrestling.⁴ Because of these potential performance enhancements, stimulant medications without appropriate documentation and approval are banned for athletes in competition by numerous athletic regulatory agencies. For example, the World Anti-Doping Agency requires that athletes taking medically necessary banned substances under physician supervision, such as stimulants for ADHD, must have a therapeutic use exemption (TUE) approved before competition. Approval can be obtained after review of the ADHD checklist¹⁶⁵ and the TUE by 2 independent consultants.¹⁶⁶ TUE approval for a new diagnosis or medication can be granted for 1 year; if the medication and dose remain constant, subsequent TUE approval may be granted for up to 4 years. Any change in medication or dosage requires resubmission of the TUE.¹⁶⁷

The NCAA also allows the use of stimulant medications with submission and approval of their ADHD-specific medical reporting form.¹⁶⁸ Documentation required by the NCAA includes the following: (1) description of the evaluation process which identifies the assessment tools and procedures; (2) statement of the diagnosis, including when it was confirmed; (3) history of ADHD treatment; (4) statement that a non-banned ADHD alternative has been considered; and (5) statement regarding follow-up and monitoring visits.¹⁶⁹ These documents and the results of the annual preparticipation evaluation are required to be updated yearly. Clinical evaluation must include a full report of family history and previous ADHD treatment in addition to ADHD rating scale scores. To ensure eligibility in the event of a positive test, the student athlete should immediately report initiation or change in medications to the institution. The institution is obligated to maintain a medical file with a record of the clinical evaluation to provide to the NCAA if needed.¹⁶⁸

Other professional athletic organizations have created individual policies regarding diagnosis, management, and documentation requirements for ADHD and use of stimulant medications in their sport. Health care professionals involved in the care of these athletes need to consult the appropriate governing body to ensure compliance with current guidelines. A summary of current organizational policies can be found in Table 7.^86,170

TABLE 7. - League- and Organization-specific Rules Related to Therapeutic Use Exemption or Pharmacologic Treatment of ADHD

League or Association	Written Policy Explicit to Stimulants for ADHD?	Stimulants Permitted?	Documentation Required	Independent Examiner Required?	Recertification Frequency and Other Documentation
MLB 170	Yes*	With TUE	ACDS Impairment scale	MLB-certified clinician or review by expert panel	Yearly, pharmacy records
MLS	No	No	N/A
NBA	No†	With TUE	Petition to the medical director of the antidrug program; medical information and valid prescription
NFL	Yes‡	With TUE	History, physical examination, and testing: Neurologic evaluation, concussion history (with imaging or neuropsychiatric testing, if indicated); evaluation for mental health disorders; laboratory tests; neurocognitive testing; interviews with player and family; DSM-V criteria; ACDS; BFIS; management plan	NFL-certified psychiatrist	Yearly; must provide documentation of follow-up visits
NHL	No†	Qualified yes	PES program committee can review, consider, and act on a player's application
NASCAR	No	With TUE
PGA	Yes	With TUE	TUE	In case of appeal, 2 arbitrators (1 appointed by the PGA tour and 1 selected by the player); these 2 select a third
ATP	Yes (follows WADA directives)	With TUE	Follows WADA directives
Boxing	Through USADA, VADA, or WADA	With TUE	Voluntary program, VADA- or WADA- administered, depending on commission and competition; VADA: Medical history/examination; laboratory results (if indicated); imaging (if indicated); WADA: DSM-V criteria; second opinion, if new diagnosis at >18 years old
MMA	Through USADA	With TUE	USADA/WADA; DSM-V criteria; second opinion if new diagnosis at >18 years old

Abbreviations: ACDS, Adult ADHD Clinician Diagnostic Scale v1.2; ADHD, attention-deficit/hyperactivity disorder; ATP, association of tennis professionals; BFIS, barkley functional impairment scales; DSM-V, diagnostic and statistical manual of mental disorders, Fifth Edition; MLB, major league baseball; MLS, major league soccer; MMA, mixed martial arts; NASCAR, National Association for Stock Car Racing; NBA, national basketball association; NFL, national football league; NHL, national hockey league; PES, performance-enhancing substance; PGA, professional golf association; TUE, therapeutic use exemption; USADA, US Anti-Doping Association; VADA, Voluntary Anti-Doping Association; WADA, World Anti-Doping Association.

^*http://mlb.mlb.com/pa/pdf/jda.pdf.

^†https://footballplayershealth.harvard.edu/wp-content/uploads/2017/05/08_Ch4_Drugs.pdf.

^‡https://nflpaweb.blob.core.windows.net/media/Default/PDFs/ADHD_requirements_2018.pdf.

Conclusions/Summary

The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition criteria for ADHD are vital for accurate diagnosis. Clinicians who care for athletes with ADHD should be aware of best practices regarding diagnosis and clinical management. Knowledge of medications used for ADHD is essential specifically regarding possible adverse effects and the rules governing their use in organized sports. Clinical recommendations for managing individuals diagnosed with ADHD are presented in Table 8.¹⁷¹ Clinicians also need to know that stimulant medications are banned by numerous athletic regulatory organizations (when used without appropriate documentation and approval) and that athletes may seek stimulants for perceived performance benefits.

TABLE 8. - Key Clinical Recommendations

Recommendations	SORT Rating 171
Use the diagnostic criteria listed in the DSM-V to diagnose ADHD.	A
Aim for a multidisciplinary approach for the treatment of ADHD, combining pharmacotherapy with cognitive and social therapies.	A
Be aware of the potential effects of stimulants, their likelihood of performance-enhancing effects in athletes, and the possibility of abuse/misuse for intended benefits.	A
Leverage thorough history, assessment scales, physical examination, cognitive tests, lab tests, and neuroimaging to rule out mimics of ADHD.	A
Identify athletes with ADHD who are at risk for cardiovascular disease and consider nonstimulant approaches to their management.	B
Adjust the dosage, timing, duration, and type of stimulant medication to address any adverse effects.	B
Ensure appropriate documentation and approval processes are followed for athletes on stimulants for ADHD competing in sports under the various athletic regulatory organizations including, but not limited to the IOC, WADA, and the NCAA.	C
Consider the interaction of ADHD and concussion, and how adequate management of 1 may positively affect outcomes/symptomatology of the other.	C
Be mindful of likelihood and unintended tendencies to underdiagnose and undertreat ADHD in girls, women, and minorities.	C

Abbreviations: ADHD, attention-deficit/hyperactivity disorder; DSM-V, diagnostic and statistical manual of mental disorders, Fifth Edition; IOC, international olympic committee; NCAA, national collegiate athletic association; SORT, strength of recommendation taxonomy; WADA, World Anti-Doping Association.

DISCLAIMER

This position statement is not intended as a clinical practice guideline or legal standard of care and should not be interpreted as such.