Educational Disclaimer: This case study is for educational and informational purposes only. It does not constitute medical advice, clinical guidance, or a substitute for professional psychiatric evaluation. All diagnostic criteria referenced are from the DSM-5-TR (APA, 2022). Clinicians should rely on their professional training, direct patient assessment, and current evidence-based guidelines when making diagnostic and treatment decisions.

Clinical Vignette

Patient: "Mr. F," 32-year-old marketing manager, self-referred after his wife gave him an ADHD article 'that described him perfectly.'

Chief Concern: "I've struggled my whole life to focus. I lose things constantly, forget appointments, can't sit through meetings. I interrupt people mid-sentence. I start projects and never finish them. I got through college on pure caffeine and all-nighters. My wife says living with me is like living with a tornado."

History of Present Illness: Mr. F reports lifelong problems with attention, organization, and impulse control. Inattention symptoms: (1) makes careless errors in reports (details missed), (2) difficulty sustaining attention in meetings (zones out within 10 minutes), (3) seems not to listen when spoken to ('drifts off mid-conversation'), (4) fails to follow through on work tasks (starts projects, does not complete), (5) difficulty organizing tasks (desk is chaotic, deadlines missed), (6) avoids tasks requiring sustained mental effort (procrastinates on report-writing until deadline), (7) loses things necessary for tasks (phone, wallet, keys — daily), (8) easily distracted by extraneous stimuli, (9) forgetful in daily activities (forgot to pick up children from school twice this month). Hyperactivity-Impulsivity: (1) fidgets with hands/feet, taps pen constantly, (2) leaves seat in meetings ('I need to walk'), (3) feels 'restless' constantly ('internal motor running'), (4) cannot engage in leisure quietly (talks during movies, fidgets while reading), (5) 'on the go' constantly ('driven by a motor'), (6) talks excessively ('I monopolize conversations'), (7) blurts out answers before questions are finished, (8) difficulty waiting turn (line-cutting, impulse purchases), (9) interrupts/intrudes on others. Childhood history confirmed by mother: 'He was exactly this way since kindergarten. Teachers called him the class tornado. He was diagnosed with 'hyperactivity' at age 7 but never treated.'

Past Psychiatric History: Childhood diagnosis of 'hyperactivity' at age 7 (untreated). No medication. Self-medicated with caffeine (4-6 cups daily).

Family History: Father: suspected ADHD (never diagnosed, 'also a tornado'). Brother: ADHD (diagnosed, on stimulant).

Mental Status Exam: Arrived 7 minutes late (lost car keys). Sat down, immediately began fidgeting. Phone on desk, picked it up 3 times during 45-minute interview. Speech rapid, voluminous. Interrupted clinician 6 times. Started answering questions before clinician finished asking. Changed topics mid-sentence 4 times. When asked to slow down, maintained slower pace for approximately 30 seconds before accelerating again. Mood 'frustrated with myself.' Affect animated. No depression, no psychosis. Insight good.

Step 1: ADHD DSM-5-TR Criteria

Criterion A — Inattention: ≥5 symptoms for adults (≥6 for children) persisting ≥6 months.

All 9 inattention symptoms present. Lifelong persistence. Far exceeds threshold. MET (9/9 inattention).

Criterion A — Hyperactivity-Impulsivity: ≥5 symptoms for adults persisting ≥6 months.

All 9 hyperactivity-impulsivity symptoms present. Lifelong persistence. MET (9/9 hyperactivity-impulsivity).

Criterion B: Several symptoms present prior to age 12.

Mother confirms identical behavior since kindergarten. Diagnosed at age 7. MET — childhood onset CONFIRMED.

Criterion C: Symptoms present in ≥2 settings.

Work (missed deadlines, careless errors, can't sit in meetings) + Home (loses things, forgets to pick up children, 'tornado'). MET — work AND home.

Criterion D: Clear evidence that symptoms interfere with or reduce quality of functioning.

Missed deadlines at work (performance reviews cite this). Marital conflict. Forgot children at school. Daily functional impairment. MET.

Criterion E: Not better explained by another mental disorder.

Not GAD (worry is not the source). Not MDD. Not substance-related. Symptoms are lifelong ADHD pattern. MET.

PRESENTATION: Combined (meets both inattention AND hyperactivity-impulsivity criteria).

9/9 inattention + 9/9 hyperactivity-impulsivity. COMBINED PRESENTATION.

Step 2: Adult ADHD Assessment Considerations

Consideration Assessment This Patient
Childhood onset requirement DSM-5-TR: several symptoms before age 12 Confirmed by mother, diagnosed at 7
Symptom threshold change Adults: ≥5 (not 6); acknowledges symptoms may attenuate ALL 9 present in both domains — clear case
Hyperactivity presentation in adults May shift from gross motor to internal restlessness Both: fidgets AND reports 'internal motor'
Compensation strategies High-IQ adults may compensate until demands exceed capacity Thrived in structured schooling, struggled in self-directed adult work
Caffeine self-medication Caffeine as stimulant self-medication is common in undiagnosed adult ADHD 4-6 cups daily — classic pattern

Functional Impact

Mr. F's ADHD produces impairment across all functional domains: occupational (missed deadlines, careless errors), marital (wife describes life as 'living with a tornado'), and parental (forgot children at school). Treatment is indicated.

Diagnostic Formulation

Diagnostic Conclusion

ADHD, Combined Presentation, Moderate (F90.2): All DSM-5-TR criteria met. Combined presentation (9/9 inattention + 9/9 hyperactivity-impulsivity). Childhood onset confirmed. Cross-setting impairment. Treatment: (1) Stimulant medication first-line (methylphenidate or amphetamine formulation — strongest evidence). (2) CBT for ADHD (organizational skills, time management, cognitive restructuring of ADHD-related self-criticism). (3) Environmental modifications (reminders, timers, structured routines). (4) Reduce caffeine intake as stimulant medication is initiated.

Teaching Points

  • DSM-5-TR changed the ADHD age-of-onset criterion from 'before age 7' (DSM-IV) to 'before age 12,' recognizing that many individuals with legitimate ADHD (particularly the predominantly inattentive presentation) are not identified until academic demands increase in later elementary school.
  • DSM-5-TR reduced the adult symptom threshold from 6 to 5 symptoms per domain, acknowledging that symptoms attenuate with age while still causing impairment. Adults may display fewer symptoms than children but still meet clinical significance.
  • Hyperactivity in adults often manifests differently than in children: children may run, climb, and be physically overactive. Adults are more likely to report INTERNAL restlessness ('motor running'), fidgeting, inability to relax, excessive talking, and difficulty with leisure activities. Mr. F displays both external (fidgeting) and internal ('driven') hyperactivity.
  • Stimulant medications (methylphenidate, amphetamines) are first-line treatment for ADHD across the lifespan. They have the strongest evidence base and largest effect sizes. Non-stimulant options (atomoxetine, guanfacine, viloxazine) are alternatives for patients who cannot tolerate or have contraindications to stimulants.
  • Self-medication with caffeine is an extremely common pattern in undiagnosed adult ADHD. Caffeine is a mild psychostimulant that provides temporary improvement in attention and focus. Mr. F's 4-6 cups daily is characteristic. This pattern often decreases once appropriate stimulant medication is initiated.