Warning signs of bipolar disorder: A clinical guide to mood episodes

How bipolar disorder affects mood and behavior

Bipolar disorder is a lifelong mental health condition involving episodes of emotional highs, known as mania or hypomania, and lows, known as depression. These shifts can influence sleep, energy, activity, judgment, behavior, and clear thinking. Episodes may occur rarely or several times a year, and each episode commonly lasts several days, although some people experience longer periods of stability between them. 1

The presence of one symptom does not establish a diagnosis. Clinicians assess the overall pattern, duration, severity, and effect on daily functioning, while also considering medical conditions, medications, and substance use that can produce similar changes. Bipolar I disorder includes at least one manic episode, while bipolar II disorder includes hypomanic and major depressive episodes without a history of mania. 1

Warning signs of mania and hypomania

Mania or hypomania may begin with an unusually elevated, euphoric, or irritable mood and a noticeable increase in energy or activity. A person may become unusually talkative, speak rapidly, move quickly between topics, experience racing thoughts, feel intensely confident, start many projects, or become more distractible and restless than usual. These changes are more significant when they represent a clear departure from the person’s usual behavior. 2

A reduced need for sleep is an important distinction from ordinary insomnia. During a manic or hypomanic period, a person may sleep much less while still feeling energetic and active. Other warning signs can include increased sexual behavior, extravagant spending, gambling, reckless driving, or other impulsive decisions. Mania is more severe than hypomania and can cause major impairment, hospitalization, or a break from reality involving hallucinations or delusions. 2 3

Warning signs of bipolar depression

Depressive episodes may involve persistent sadness, hopelessness, emptiness, or a loss of interest and pleasure in activities that previously mattered. Affected individuals can also experience fatigue, reduced motivation, difficulty concentrating, feelings of worthlessness or guilt, and changes in sleep or appetite. These symptoms can interfere with work, education, relationships, personal care, and other routine responsibilities. 4

Depression associated with bipolar disorder can be difficult to distinguish from other depressive conditions based on symptoms alone. The history of elevated or irritable episodes, changes in energy, reduced need for sleep, and impulsive behavior is therefore clinically important. Thoughts about death or suicide are serious warning signs, regardless of whether they occur during depression, a mixed state, or another mood episode. 5

Mixed features and early changes

Some people experience mixed features, meaning symptoms associated with depression and mania or hypomania occur during the same period. Examples include sadness or hopelessness alongside agitation, racing thoughts, unusually high energy, irritability, or markedly reduced sleep. This combination can be especially disruptive because emotional distress occurs at the same time as heightened activation and impaired judgment. 4

Early changes may be subtle, particularly in teenagers. Sleep disruption, shifts in energy, irritability, and racing thoughts can precede a full mood episode, especially when there is a family history of bipolar disorder. Adolescents also commonly experience intense reactions to ordinary stressors, so clinicians examine whether mood changes are persistent, severe, and outside the person’s typical pattern rather than assuming that every fluctuation indicates bipolar disorder. 6 7

Patterns that merit professional assessment

Concern is greater when mood changes are episodic, appear without a clear trigger, and substantially alter sleep, energy, speech, activity, judgment, or relationships. Repeated cycles between elevated and depressed states, unexplained periods of unusually high productivity or confidence, and behavior that others describe as uncharacteristic can provide useful information for an assessment. Keeping a record of sleep, mood, energy, medications, substances, and major behavior changes may help clarify the pattern. 8

Family observations can be valuable because mania or hypomania may feel positive or productive to the person experiencing it, while relatives notice escalating arguments, spending, risky decisions, or increasingly rapid speech. A healthcare professional may also investigate whether symptoms began after substance exposure, withdrawal, or medication use. Substance-induced mood symptoms and bipolar disorder require different clinical considerations, making an accurate history important. 4 9

When symptoms require urgent help

Urgent help is warranted when symptoms involve suicidal thoughts, hallucinations, delusions, dangerous impulsivity, inability to care for basic needs, or an imminent risk of harm to the person or someone else. Severe mania can impair judgment and reality testing, while severe depression can compromise safety and daily functioning. Psychosis, escalating threats, and rapidly worsening behavior should be treated as medical concerns rather than as ordinary moodiness. 2

In the United States, the 988 Suicide and Crisis Lifeline accepts calls and texts for suicide, mental-health, and substance-use crises. Emergency services may be appropriate when there is immediate danger. Outside the United States, crisis procedures vary by location, so local emergency or urgent mental-health services provide the relevant route. Bipolar disorder is treatable, and care commonly involves medication, psychotherapy, monitoring, and support tailored to the individual’s symptoms and risks. 10 11

Sources

1. Mayo Clinic, Bipolar disorder: Symptoms and causes
2. Cleveland Clinic, Bipolar Disorder: What It Is, Symptoms & Treatment
3. Pathlight Behavioral Health, Warning Signs of Bipolar Disorder
4. Merck Manual Professional Edition, Bipolar Disorders
5. NCBI Bookshelf, Bipolar disorder: assessment and management
6. Child Mind Institute, Early Signs of Bipolar Disorder in Teens
7. University of Utah Health, Bipolar Symptoms in Teens: Early Signs and Diagnosis
8. National Institute of Mental Health, Bipolar Disorder
9. National Health Service, Bipolar disorder: Symptoms
10. American Psychiatric Association, Bipolar Disorders
11. Substance Abuse and Mental Health Services Administration, 988 Suicide & Crisis Lifeline