ADHD or Bipolar Disorder? How the Two Are Told Apart

Updated October 13, 2026. Part of the New York Adult ADHD Guide, understand section. Medically reviewed by John C. Shershow, M.D. on October 13, 2026. Editorial policy

Key points

A 2021 meta-analysis of 71 studies found that 7.95% of adults with ADHD have bipolar disorder and 17.11% of adults with bipolar disorder have ADHD.
ADHD criteria require several symptoms before age 12; the National Institute of Mental Health says bipolar symptoms most often start in late adolescence or early adulthood.
A manic episode in bipolar I disorder lasts at least seven days or is severe enough to need hospital care, according to NIMH.
FDA labels for stimulants direct prescribers to screen patients for risk factors for a manic episode before starting treatment.
A 2024 study of hospitalized patients aged 16 to 35 linked recent prescription amphetamine use with higher odds of first-episode psychosis or mania and found no such link for methylphenidate.

Talking fast, jumping between projects, sleeping little, acting on impulse, being easily distracted: these describe ADHD, and they also describe a manic or hypomanic episode. Adults are sometimes given one diagnosis when the other fits better, and some have both. This page explains the distinction clinicians draw and why they draw it before prescribing.

Why the two get confused

The National Institute of Mental Health (NIMH) describes manic episodes as including racing thoughts, talking fast, a decreased need for sleep, extreme irritability and feeling very up or elated. Its description of bipolar depression includes trouble concentrating. Each of those has a counterpart in ADHD: distractibility, excessive talking, restlessness, low frustration tolerance.

NIMH also states that bipolar disorder can be misdiagnosed and that it often co-occurs with ADHD, anxiety disorders and substance misuse. A snapshot of symptoms on one day cannot separate the conditions. A history can.

The central difference: episodes versus a lifelong pattern

Feature	ADHD	Bipolar disorder
When it starts	Several symptoms before age 12	Most often late adolescence or early adulthood
Course	Continuous, with ups and downs tied to demands and stress	Distinct episodes, with periods of usual functioning between them
Duration markers	Symptoms for at least six months	Bipolar I: manic episodes lasting at least seven days, or severe enough to need hospital care. Depressive episodes typically last at least two weeks
Mood	Not a defining feature of the criteria	Defining feature: very elevated or irritable mood in mania, very low mood in depression
Sleep	Often takes longer to fall asleep; the need for sleep is unchanged	In mania, a decreased need for sleep
Self-regard	No characteristic change	In mania, feeling unusually important or powerful

The bipolar rows come from NIMH's descriptions. The ADHD rows on onset and duration come from the diagnostic criteria as NIMH summarizes them. The sleep contrast draws on a 2018 meta-analysis showing that adults with ADHD take longer to fall asleep and sleep less efficiently.

The question clinicians return to is whether this is how the person has always been, or whether it is a change. ADHD is the baseline. A manic or hypomanic episode is a departure from baseline that other people usually notice.

Bipolar II and hypomania

The distinction is hardest with bipolar II disorder. NIMH describes it as a pattern of depressive and hypomanic episodes, where hypomania is a milder form of mania that does not interfere as much with daily life. The person may feel very good and productive and not realize anything is wrong. A few energetic, sleepless, talkative days can pass for "my ADHD acting up" unless someone asks how those days differ from an ordinary week.

How often they occur together

A 2021 meta-analysis pooled 71 studies covering 646,766 people. It found that 7.95% of adults with ADHD also have bipolar disorder, about 1 in 13, and that 17.11% of adults with bipolar disorder also have ADHD, about 1 in 6.

An older US survey from 2006 reported a higher figure, about 19% of adults with ADHD having bipolar disorder in the previous year. That estimate came from a small sample with wide error margins. The 2021 meta-analysis is larger and newer, and this guide treats it as the better estimate.

Either way, having both is far from rare. A diagnosis of one does not rule out the other.

Stimulants, mania and psychosis: what the evidence shows

FDA labels for stimulant medications tell prescribers to screen patients for risk factors for developing a manic episode before starting treatment, and to consider stopping the medication if new psychotic or manic symptoms appear. The label for the non-stimulant atomoxetine carries a similar warning about new psychotic or manic symptoms.

The largest recent study on the question was published in the American Journal of Psychiatry in 2024. Researchers at McLean Hospital examined patients aged 16 to 35 hospitalized between 2005 and 2019: 1,374 with a first episode of psychosis or mania, compared with 2,748 patients hospitalized for other psychiatric reasons.

Past-month use of a prescription amphetamine was associated with higher odds of first-episode psychosis or mania (adjusted odds ratio 2.68).
The odds were highest at the top dose level studied.
Methylphenidate use showed no association (adjusted odds ratio 0.91).

The limits are substantial. Everyone in the study was a young psychiatric inpatient in one hospital system, the comparison group was also hospitalized, and the design was case-control. The study does not give an absolute risk for a typical adult outpatient, and it does not show that stimulants cause psychosis. It does support careful screening, attention to dose and prompt reporting of new symptoms.

Seek urgent help for a sharply reduced need for sleep with high energy, beliefs or perceptions others say are not real, or reckless behavior that is out of character. Call or text 988 at any hour, or 911 in an emergency.

What happens when both are present

The sources reviewed for this guide do not set out a fixed sequence for treating ADHD and bipolar disorder together, and the first US adult ADHD guideline had not been published as of October 13, 2026. Some points are established:

NIMH states that mood stabilizers can help prevent mood episodes or reduce their severity.
NIMH also states that antidepressants are not used alone in bipolar disorder because they can trigger a manic episode or rapid cycling. That is one reason an accurate diagnosis comes before any prescription for low mood or poor focus.
Stimulant labels require screening for mania risk before treatment begins.

Taken together, these explain why a prescriber asks in detail about mood history before starting ADHD medication and watches closely afterward. Decisions about specific medications are individual and belong to the treating prescriber.

What an evaluator will ask

Have you ever had a period of days when you needed far less sleep and still had more energy than usual?
During such periods, did you spend, drive, talk or take risks in ways that were unlike you?
Did other people comment on the change?
Has anyone in your family been diagnosed with bipolar disorder?
Have you ever been hospitalized for a psychiatric reason?
How did you react to antidepressants, stimulants or steroids in the past?
What were your attention and activity level like in elementary school?

A partner or relative who has known you for years can often describe episodes more accurately than you can from the inside. The practice's evaluation page explains how that information is gathered.

Related pages in this guide: ADHD and depression in adults and what the major treatment studies found. The ADHD and Related Conditions hub covers anxiety and stress. If you already carry one diagnosis and doubt it, the comparison to read next is when to get a second opinion.

Questions

Can you have both ADHD and bipolar disorder?

Yes. A 2021 meta-analysis found bipolar disorder in about 1 in 13 adults with ADHD and ADHD in about 1 in 6 adults with bipolar disorder. Each condition is diagnosed on its own criteria.

Can ADHD be misdiagnosed as bipolar disorder, or the reverse?

Yes, in both directions, because distractibility, rapid speech, restlessness and impulsivity appear in both. NIMH notes that bipolar disorder can be misdiagnosed. A careful history of episodes versus a lifelong pattern is what separates them.

Can stimulants trigger mania?

Stimulant labels tell prescribers to screen for mania risk factors before treatment and to consider stopping the drug if manic or psychotic symptoms appear. A 2024 hospital study found higher odds of first-episode psychosis or mania with recent prescription amphetamine use and none with methylphenidate, in young inpatients.

Are mood swings a symptom of ADHD?

Mood is not part of the formal diagnostic criteria for ADHD, though many adults with ADHD describe quick shifts in frustration and mood. Bipolar episodes are different in kind: NIMH describes manic episodes lasting at least seven days and depressive episodes typically lasting at least two weeks.

Does a family history of bipolar disorder mean I cannot take ADHD medication?

Not automatically. Family history is one of the things a prescriber weighs when screening for mania risk, as stimulant labels direct. It affects how carefully treatment is chosen and monitored, and the decision is made case by case.

Sources

This article is general information, not medical or legal advice. Rules and coverage change; check the linked sources for the current position, and speak with a clinician or attorney about your own situation.