1. The natural course of untreated ADHD
ADHD persists into adulthood for roughly 60-70% of children when measured by impairment criteria (Faraone & Larsson, 2019). The presentation evolves - hyperactivity attenuates, inattention and executive dysfunction often persist - but the underlying self-regulation deficits do not reliably "burn out." Untreated, those deficits map onto measurable population-level harms: suicide, substance use disorders, school failure, motor vehicle crashes, criminal convictions, and a roughly doubled all-cause mortality rate (Dalsgaard et al., Lancet 2015).
The full review of those harms - with the Sultan 2021 NCS-A analysis as the anchor - is on the companion page: Adverse Outcomes of Untreated ADHD. This page focuses on what changes when treatment is initiated.
2. Population-level evidence that treatment changes the course
The cleanest evidence comes from within-individual designs: studies that compare the same person to themselves across periods on and off medication. These designs control for the stable confounders (genetics, family environment, baseline severity) that haunt observational psychiatric epidemiology.
Sultan, Saunders, Veenstra-VanderWeele, JAMA Psychiatry 2025
Our 2025 commentary (doi:10.1001/jamapsychiatry.2025.0918) reviewed Li et al.'s Swedish self-controlled case series of 247,420 individuals with ADHD followed from 2006-2020. The headline within-individual findings:
| Outcome | Reduction in women | Reduction in men | Source |
|---|---|---|---|
| Criminal convictions | ↓ 41% | ↓ 32% | Li 2024 / Lichtenstein 2012 |
| Substance-related ED events | ↓ 31% | ↓ 35% | Li 2024 / Quinn 2017 |
| Motor vehicle crashes | ↓ 42% | ↓ 38% | Li 2024 / Chang 2017 |
| Suicidal behavior | Meaningful within-individual reduction | Li 2024 | |
Boland meta-analysis (across outcomes)
A pooled analysis across mood disorders, substance use disorders, accidents, crime, injuries, and educational outcomes estimated approximately 25-35% improvement during active treatment and ~50% improvement comparing treated to never-treated groups. The signal is robust across outcome categories, study designs, and countries.
Why this matters
"Symptom reduction" is the standard endpoint for ADHD pharmacotherapy trials. But symptom reduction is not the same as a changed life trajectory. The studies above measure trajectory directly: did the person get arrested, hospitalized, in a crash, or admitted to an emergency room less often during periods when they were taking medication? The answer is consistently yes, by 30-40% across outcomes that drive the bulk of ADHD's population-level harm.
3. Cardiovascular safety
The most common worry families bring to me is cardiovascular safety. The data are reassuring at population scale.
Population studies
- Zhang et al. (2023, JAMA Psychiatry) – A Swedish national cohort of 278,027 individuals with ADHD found no significant increase in serious cardiovascular events with stimulant treatment over a 14-year follow-up. (See full discussion on the existing blog: ADHD Cardiovascular Safety.)
- Cooper et al. (2011, NEJM) – A retrospective cohort of 1.2 million U.S. children and young adults found no association between current stimulant use and serious cardiovascular events.
- Habel et al. (2011, JAMA) – A cohort of 443,198 U.S. adults found no increased risk of serious cardiovascular events with current ADHD medication use.
Mean physiologic effects
Stimulants produce mean increases of approximately 5-10 bpm in heart rate and 2-5 mmHg in blood pressure. These are small in absolute terms and stabilize in most patients within weeks. Routine cardiovascular monitoring (baseline history, vital signs at follow-up, attention to family history of sudden cardiac death) is standard of care.
4. Stimulants and substance use risk: the "gateway" question
The persistent worry that giving children stimulants will lead to later substance use is one of the most studied questions in ADHD pharmacotherapy. The data are unambiguous in the opposite direction.
- Quinn et al. (2017, Am J Psychiatry) – Within-individual analysis of 2.99 million U.S. patients with ADHD (MarketScan): 31-35% lower substance-related emergency visits during medicated months.
- Wilens et al. (2003 meta-analysis) – Pooled analysis of children treated with stimulants found no increase, and a likely decrease, in later substance use disorder.
- Li et al. (2024) / Sultan et al. (2025) – Replication in Swedish national data, with substance-related ED reductions of 31-35%.
The mechanism is consistent with what the basic science predicts: stimulants reduce impulsivity and improve executive control - the same capacities that, when impaired, drive impulsive substance use in untreated ADHD. (See the related blog post on stimulant medications and substance use protection for a single-study walk-through, and the ADHD & Substance Use hub page.)
5. Pediatric and adult prescribing patterns
Population pharmacology safety depends not just on the molecules but on how they are prescribed. Two of my own studies map the patterns.
Sultan et al., J Child Adolesc Psychopharmacol 2018
Using the IMS LifeLink LRx longitudinal database (6.35 million filled prescriptions), we mapped annual psychotropic prescribing rates by age:
| Age band | Any psychotropic (annual) | Stimulant peak |
|---|---|---|
| 3-5 years | 0.8% | Low |
| 6-12 years | 5.4% | Rising; peak at age 11 (5.7%) |
| 13-18 years | 7.7% | Plateau |
| 19-24 years | 6.0% | Declining; antidepressants rising |
The implication: stimulant prescribing is concentrated in the developmentally appropriate window, and the practical pharmacology-safety question for clinicians is less "should we treat at all" than "are we titrating, monitoring, and discontinuing on the right cadence."
Sultan et al., JAMA Network Open 2019 (440+ citations)
In MarketScan data on 187,563 U.S. youth with new ADHD diagnoses, we found that 2.6% were prescribed an antipsychotic in the year following diagnosis - meaningfully higher than general-population rates. 47.9% of antipsychotic-treated youth had not received a stimulant trial first, contrary to evidence-based practice. Antipsychotic-treated youth were substantially more likely to have recent diagnoses of self-harm/suicidal ideation (aOR 7.5), oppositional defiant disorder (aOR 4.4), substance use disorder (aOR 4.0), and recent inpatient mental health treatment (aOR 7.9).
The clinical interpretation: when first-line stimulant pharmacology is skipped or aborted prematurely, the next escalation tends to be a class with a worse metabolic and adverse-effect profile. Getting the stimulant trial right - dose, duration, formulation, monitoring - is itself a safety intervention.
6. When pharmacology fails or harms
Honest pharmacology safety has to address the cases where treatment does not work well or causes harm. The major categories:
Side effects
The full management guide is at ADHD Medication Side Effects. The most common - decreased appetite, insomnia, headache, jitteriness - are usually manageable with dose, timing, and formulation adjustments. Most improve substantially within 2-4 weeks.
Tolerance and apparent loss of effect
True pharmacologic tolerance to stimulants is uncommon. More often, apparent tolerance reflects increased life demands, sleep deprivation, or under-dosing relative to growth. See ADHD Medication Tolerance for the differential.
Drug holidays
Weekend or summer holidays from stimulants are sometimes appropriate for growth concerns or specific patient preferences. They are not, in general, required. See ADHD Drug Holidays.
When to switch classes
If methylphenidate at adequate dose is poorly tolerated or ineffective, the evidence supports trying an amphetamine before moving to non-stimulants. The 47.9% finding above (Sultan 2019) is in part a finding about prescribers skipping this step.
When pharmacology truly fails
For a minority of patients, stimulants and non-stimulants both fail to provide acceptable benefit-to-side-effect balance. The next decisions involve careful re-evaluation of the diagnosis, treatment of comorbid conditions that may be driving impairment, and integration of behavioral, psychotherapeutic, and lifestyle interventions. See ADHD Therapy Comparison and ADHD Alternative Treatments.
7. Clinical takeaway
The pharmacology-safety case for treating ADHD is the population-level case. Symptom-rating-scale improvement is the standard trial endpoint, but it understates what treatment actually does. The within-individual evidence shows that pharmacotherapy is associated with 30-40% reductions in the outcomes that drive most of ADHD's population-level harm - convictions, substance-related emergencies, motor vehicle crashes, suicidal behavior. Cardiovascular risks at population scale are small. Stimulants reduce, not increase, later substance use risk.
That changes the framing. The default question is not "should we treat" but "are we titrating, monitoring, and discontinuing well, and are we attending to the comorbid conditions that drive much of the residual impairment?" When pharmacology is done well, it is one of the most effective interventions in psychiatry by any honest measure of what matters in patients' lives.
— Ryan S. Sultan, MD
Read the companion review
The detailed evidence on what untreated ADHD costs at population scale - the Sultan 2021 NCS-A findings, mortality data, and supporting literature.
Adverse Outcomes of Untreated ADHD →8. Frequently asked questions
Are ADHD medications safe long-term?
Yes, when prescribed and monitored appropriately. Population-scale studies covering hundreds of thousands of patient-years show that the cardiovascular risks of stimulants are small in absolute terms, and within-individual analyses show substantial benefits during medicated periods.
Do ADHD stimulants increase substance abuse risk?
No. Quinn 2017 found 31-35% lower substance-related emergency events during medicated months. The 'gateway' framing is not supported by the data.
How does ADHD medication change the natural course of the disorder?
Within-individual analyses show 32-41% fewer criminal convictions, 31-35% fewer substance-related emergencies, 38-42% fewer motor vehicle crashes, and meaningful reductions in suicidal behavior during treated periods.
Are ADHD medications cardiotoxic?
Stimulants produce small mean increases in HR (5-10 bpm) and BP (2-5 mmHg). Population studies find no significant increase in serious cardiovascular events. Standard monitoring applies; structural heart disease warrants cardiology consultation.
Can ADHD medication reduce mortality?
Plausibly. The excess ADHD mortality (Dalsgaard 2015) is driven by accidents - the same outcome category that medication reduces by 38-42%. Li 2024 analyzed mortality directly and found reductions during medicated periods.
How long should someone take ADHD medication?
There is no fixed duration. ADHD is chronic; treatment is generally maintained as long as it is providing benefit and is well-tolerated. Discontinuation decisions are individualized.
Do ADHD medications cure ADHD?
No. They treat but do not cure. Symptoms typically return when medication is stopped. The clinical question is not cure, but whether sustained treatment changes the trajectory of downstream harms - which it does.
References
- Sultan RS, Saunders DC, Veenstra-VanderWeele J. Protective effects of ADHD medication on real-world outcomes. JAMA Psychiatry. 2025. doi:10.1001/jamapsychiatry.2025.0918
- Sultan RS, Wang S, Crystal S, Olfson M. Antipsychotic Treatment Among Youths With Attention-Deficit/Hyperactivity Disorder. JAMA Network Open. 2019;2(7):e197850. doi:10.1001/jamanetworkopen.2019.7850
- Sultan RS, Correll CU, Schoenbaum M, King M, Walkup JT, Olfson M. National Patterns of Commonly Prescribed Psychotropic Medications to Young People. J Child Adolesc Psychopharmacol. 2018;28(3):158-165. doi:10.1089/cap.2017.0077
- Li L, Zhu N, Zhang L, et al. ADHD pharmacotherapy and adverse outcomes: a Swedish self-controlled case series, N=247,420. 2024.
- Lichtenstein P, Halldner L, Zetterqvist J, et al. Medication for attention deficit-hyperactivity disorder and criminality. N Engl J Med. 2012;367(21):2006-2014.
- Chang Z, Quinn PD, Hur K, et al. Association between medication use for attention-deficit/hyperactivity disorder and risk of motor vehicle crashes. JAMA Psychiatry. 2017;74(6):597-603.
- Quinn PD, Chang Z, Hur K, et al. ADHD medication and substance-related problems. Am J Psychiatry. 2017;174(9):877-885.
- Zhang L, Yao H, Li L, et al. Risk of cardiovascular diseases associated with medications used in attention-deficit/hyperactivity disorder. JAMA Psychiatry. 2024;81(2):178-187.
- Cooper WO, Habel LA, Sox CM, et al. ADHD drugs and serious cardiovascular events in children and young adults. N Engl J Med. 2011;365(20):1896-1904.
- Habel LA, Cooper WO, Sox CM, et al. ADHD medications and risk of serious cardiovascular events in young and middle-aged adults. JAMA. 2011;306(24):2673-2683.
- Wilens TE, Faraone SV, Biederman J, Gunawardene S. Does stimulant therapy of attention-deficit/hyperactivity disorder beget later substance abuse? A meta-analytic review of the literature. Pediatrics. 2003;111(1):179-185.
- Faraone SV, Larsson H. Genetics of attention deficit hyperactivity disorder. Mol Psychiatry. 2019;24(4):562-575.
- Dalsgaard S, Østergaard SD, Leckman JF, Mortensen PB, Pedersen MG. Mortality in children, adolescents, and adults with attention deficit hyperactivity disorder: a nationwide cohort study. Lancet. 2015;385(9983):2190-2196.
Considering ADHD treatment?
Dr. Sultan provides ADHD evaluation and pharmacologic management at Columbia University Medical Center in New York City.
Request ConsultationAbout Dr. Ryan Sultan
Dr. Ryan Sultan is Assistant Professor of Clinical Psychiatry at Columbia University Irving Medical Center, Director of the Sultan Lab for Mental Health Informatics, and a board-certified Adult and Child/Adolescent psychiatrist. His research focuses on two questions: (1) what happens to people with untreated ADHD, and (2) how pharmacologic treatment changes that trajectory.
His 2025 JAMA Psychiatry commentary with Saunders and Veenstra-VanderWeele (the anchor paper for this review) documented how medication reduces criminal convictions, substance-related emergency visits, and motor vehicle crashes by 30-42%. His 2021 Journal of Adolescent Health study quantified the adverse-outcome burden of untreated ADHD. His 2019 JAMA Network Open study on antipsychotic prescribing in youth with ADHD has been cited 440+ times.