Key Takeaways
- ADHD is a steady, lifelong pattern that begins in childhood; bipolar disorder comes in distinct episodes that usually begin in the late teens or twenties.
- Sleep is a strong clue: in hypomania or mania people need less sleep and do not feel tired, while people with ADHD often struggle to settle and then feel exhausted.
- The two often occur together: in one large analysis, about 1 in 6 adults with bipolar disorder also had ADHD.
- When both are present, mood is usually stabilized before ADHD medication is considered, because a stimulant taken without a mood stabilizer has been linked to mania.
- For Texas patients, Schedule II stimulant prescriptions are written by the collaborating physician who works with Dr. Forbes.
ADHD and bipolar disorder can look alike in a single conversation: both can involve distractibility, restlessness, fast talking, impulsive decisions and trouble sleeping. The clearest difference is time. ADHD is a constant pattern that has been present since childhood, in good weeks and bad. Bipolar disorder arrives in episodes, stretches of days or weeks when energy, mood and sleep shift noticeably away from your usual self, with periods of depression in between. Many adults have both. This page explains how clinicians tell them apart, how often they overlap, and why the order of treatment matters.
Why the two get confused
Several features show up in both conditions, which is why NICE lists ADHD among the conditions to consider when bipolar disorder is suspected, and why the reverse is true when adults are assessed for ADHD.
| Feature | More typical of ADHD | More typical of bipolar disorder |
|---|---|---|
| Course over time | Constant since childhood | Distinct episodes with a clear before and after |
| Distractibility | Lifelong; worse when bored | Rises sharply during a high period |
| Talking a lot | Habitual, often interrupting | Faster and harder to interrupt than usual for that person |
| Sleep | Hard to wind down; tired the next day | Needs much less sleep and still feels energetic |
| Mood | Frustration or boredom tied to events | Elevated, expansive or irritable mood lasting days |
| Self-image | Often self-critical after years of struggle | Can become unusually grand during episodes |
| Depression | Can occur, often linked to setbacks | Episodes of two weeks or more are common |
None of these rows decides anything alone. The pattern across your whole history is what counts.
The biggest clue: steady pattern or episodes
NIMH describes ADHD as a neurodevelopmental condition whose symptoms begin in childhood and usually continue into adulthood. Someone with ADHD can usually say, "I have always been like this." Report cards, a parent’s memories and long-standing habits tell the story.
Bipolar disorder is different. The American Psychiatric Association puts the average age of onset in the mid-20s, and the illness shows up as episodes. A person may describe a week of barely sleeping, launching three businesses and spending heavily, then months of normal functioning, then a deep depression. Between episodes, attention and energy often return close to baseline. If your focus problems are worse during some stretches and fine during others, that pattern deserves attention.
Our sibling page on ADHD vs bipolar disorder in children and teens covers how this looks earlier in life, where telling them apart is harder.
Sleep, energy and mood
Sleep is one of the most useful questions a clinician asks. In hypomania and mania, people feel rested after a few hours and do not miss the lost sleep. Many adults with ADHD also sleep poorly, but the experience is different: the mind will not switch off, bedtime keeps slipping, and the next day feels like dragging through fog. Our page on sleep and bipolar disorder explains why reduced need for sleep is such an important warning sign.
Mood offers another clue. ADHD frustration usually flares in response to something, such as a missed deadline or a long meeting, and settles within hours. A bipolar high or irritable stretch has its own momentum and lasts days, often with others noticing that you are not your usual self.
Having both: how common it is
Overlap is common. A 2021 meta-analysis found that about 1 in 6 adults with bipolar disorder (17.1%) also met criteria for ADHD, and about 1 in 13 adults with ADHD (7.95%) had bipolar disorder. When both were present, bipolar disorder started about four years earlier on average. NIMH lists ADHD among the conditions that frequently occur alongside bipolar disorder.
Having both is not a sign that one diagnosis is wrong. It means the evaluation has to separate what is lifelong from what comes and goes, so each condition gets the right treatment at the right time.
Hyperfocus, productive bursts and hypomania
Adults with ADHD often describe hyperfocus: hours absorbed in something interesting, losing track of time and meals. That can sound like the drive of hypomania, but the two behave differently. Hyperfocus is pulled by interest and ends when the task does or the interest fades; it can happen any day of the year. Hypomania is a change in the whole person for days at a time, with more energy across many activities, less need for sleep and often a lift in confidence or irritability that others comment on.
Another common mix-up is the productive stretch that follows a new job, relationship or medication. A burst of motivation after a positive change is not, by itself, hypomania. The questions a clinician asks are how long it lasted, whether sleep dropped without fatigue, and whether the people around you saw you as noticeably different. If those answers are yes, the stretch is worth describing in detail at an evaluation.
How an evaluation sorts it out
- Childhood history. ADHD criteria reach back to childhood, so school experiences and family memories matter. Our guide to the adult ADHD evaluation explains what that assessment covers.
- A mood timeline. Mapping high and low periods over the years shows whether symptoms cluster into episodes.
- Input from others. A partner or parent can often say whether the restlessness has always been there or appeared in bursts.
- Rule-outs. Thyroid problems, substances, poor sleep, anxiety and depression all affect focus.
- Medication history. A past antidepressant or stimulant that triggered agitation, sleeplessness or a high stretch is an important clue.
Our page on how bipolar disorder is diagnosed walks through those steps in more detail.
Treatment when both are present
The usual order is mood first. A 2017 Swedish registry study followed 2,307 adults with bipolar disorder who started methylphenidate, a common ADHD stimulant. Those taking it without a mood-stabilizing medication had a markedly higher rate of manic episodes in the following three months (hazard ratio 6.7). Those already taking a mood stabilizer showed no increase; their rate was actually lower (hazard ratio 0.6). The authors concluded that bipolar disorder should be carefully ruled out before a stimulant is started on its own.
In practice, that means stabilizing mood, often with one of the mood stabilizers or another mood-stabilizing medication, and then reassessing attention. Some symptoms that looked like ADHD improve once mood is steady. If they do not, ADHD treatment can be considered, with close watch for changes in sleep and mood. Non-stimulant options and skills-based approaches are part of that conversation; our page on whether ADHD medication is right for you covers the broader decision.
Do not start, stop or change any of these medications on your own. Stopping a mood stabilizer suddenly raises the risk of relapse.
At Willow & Stone
Dr. Stacey Forbes, a board-certified psychiatric-mental health nurse practitioner, evaluates adults for both conditions at the same 90-minute evaluation, and medication options are discussed there once the picture is clear. For Texas patients, Schedule II stimulant prescriptions are written by the collaborating physician who works with Dr. Forbes. Learn more about bipolar disorder treatment at Willow & Stone, or browse the bipolar disorder guide for background on the condition.
Common Questions
Can ADHD be mistaken for bipolar disorder?
Yes, in both directions. Restlessness, distractibility, fast talking and impulsive choices appear in both. The key difference is that ADHD is constant from childhood, while bipolar disorder comes in episodes lasting days or weeks with changes in sleep and mood. A careful history usually separates them.
Can you have ADHD and bipolar disorder at the same time?
Yes. In a 2021 meta-analysis, about 17% of adults with bipolar disorder also had ADHD, and about 8% of adults with ADHD had bipolar disorder. Both can be treated, usually by stabilizing mood first and then reassessing attention.
Can ADHD stimulants cause mania?
They can in people with bipolar disorder who are not taking a mood stabilizer. A large Swedish registry study found a much higher rate of mania after starting methylphenidate alone, but no increase in people already on a mood-stabilizing medication. That is why bipolar disorder is ruled out before a stimulant is started.
Are racing thoughts a sign of ADHD or bipolar disorder?
Either, and also anxiety. In ADHD, a busy mind is a long-standing trait. In hypomania or mania, thoughts speed up noticeably for days at a time, often with less need for sleep and more energy. What matters is whether the change is constant or comes in distinct stretches.
Can bipolar disorder be misdiagnosed as ADHD?
Yes. If an evaluation focuses only on current focus and restlessness, a hypomanic stretch can be read as ADHD, and a stimulant started on its own may then trigger mania. Asking about past episodes, sleep changes and family history of bipolar disorder before any ADHD medication helps prevent that.
Is there a test for ADHD vs bipolar disorder?
No single test separates them. Questionnaires can screen for each condition, but the distinction rests on a clinical evaluation of when symptoms started, whether they come in episodes, and what else could explain them. Lab tests can rule out causes such as thyroid problems.
Part of our bipolar disorder guide
Sources & Further Reading
- Schiweck C et al. Comorbidity of ADHD and adult bipolar disorder: systematic review and meta-analysis. Neurosci Biobehav Rev 2021
- Viktorin A et al. The risk of treatment-emergent mania with methylphenidate in bipolar disorder. Am J Psychiatry 2017
- NIMH: Attention-Deficit/Hyperactivity Disorder (reviewed August 2026)
- NIMH: Bipolar Disorder (NIH Pub. 25-MH-8088, revised 2025)
- American Psychiatric Association: What Are Bipolar Disorders? (reviewed April 2024)
- NICE CG185: Bipolar disorder, assessment and management (last updated 2 Sept 2025)
This article is general education, not a diagnosis or advice for your situation. Do not start, stop, or change a medication without talking to the clinician who prescribes it; stopping a mood stabilizer suddenly can trigger relapse.
If you need help right now
Willow & Stone is an outpatient practice and is not an emergency service. If you or someone you care about is in immediate danger, call 911.
For urgent mental health support at any hour, call or text 988 to reach the Suicide & Crisis Lifeline, or text HOME to 741741 for the Crisis Text Line. Both are free, confidential, and available 24/7 nationwide.
Dr. Stacey Forbes, DNP, APRN, PMHNP-BC
Board-certified Psychiatric-Mental Health Nurse Practitioner and founder of Willow & Stone Integrative Mental Health. Nearly two decades of clinical experience; integrative, root-cause psychiatry in person in Arlington and by telehealth. Licensed in Texas, New Mexico, Florida, Alaska, Arizona, Colorado & Washington.
About Dr. Forbes →