Bipolar Disorder: Symptoms, Causes, and Its Connection to Substance Use

What Is Bipolar Disorder?

Bipolar disorder causes unusual and often intense shifts in mood, energy, activity level, concentration, and the ability to carry out everyday tasks. These are not the ordinary ups and downs most people experience — a bipolar mood episode typically lasts a week or more (sometimes considerably longer) and represents a real departure from a person's usual functioning. The condition includes a few distinct types.

• Bipolar I disorder, defined by at least one manic episode lasting at least a week (or any duration if hospitalization is required), which may be preceded or followed by hypomanic or major depressive episodes. Manic episodes can be severe enough to require hospitalization and can include psychotic features in some cases.
• Bipolar II disorder, defined by a pattern of at least one major depressive episode and at least one hypomanic episode lasting at least four consecutive days, without the full manic episodes seen in bipolar I. Hypomania is a less intense version of mania — someone may feel unusually good and function well during it, but the mood is not stable, and depression often follows.
• Cyclothymic disorder (cyclothymia), marked by numerous periods of hypomanic and depressive symptoms lasting at least two years in adults (one year in children and adolescents) that do not meet the full intensity or duration criteria for hypomanic or major depressive episodes.
• Other specified and unspecified bipolar and related disorders, a category used when symptoms do not fit neatly into the patterns above, including bipolar-like symptoms that may be triggered by certain medications, other substances, or another medical condition.

Some people also experience a "mixed" episode or "mixed features," where manic and depressive symptoms occur together or in rapid succession — for example, feeling agitated and full of racing thoughts while also feeling hopeless. Rapid cycling, defined as four or more mood episodes within a 12-month period, is another pattern that can occur with any type of bipolar disorder and is generally associated with a more difficult course.

Symptoms of a Manic, Hypomanic, and Depressive Episode

Manic and hypomanic episodes commonly involve an unusually elevated, expansive, or irritable mood alongside increased energy, plus at least several of the following: inflated self-esteem or grandiosity, a decreased need for sleep (feeling rested after very little sleep), being more talkative than usual or feeling pressure to keep talking, racing thoughts or a rapid flow of ideas, being easily distracted, an increase in goal-directed activity or physical restlessness, and engaging in activities that carry a high potential for painful consequences, such as unrestrained spending, impulsive sexual behavior, or risky business decisions. The distinction between mania and hypomania is largely about severity and impact: mania is severe enough to markedly impair functioning, often requires hospitalization, and may include psychotic symptoms; hypomania is noticeable to others but does not cause the same level of impairment.

Depressive episodes in bipolar disorder look similar to major depressive disorder — persistent sadness, emptiness, or hopelessness, loss of interest or pleasure in nearly all activities, significant changes in weight or appetite, sleeping too much or too little, fatigue or loss of energy, feelings of worthlessness or excessive guilt, difficulty concentrating or making decisions, restlessness or slowed movements noticeable to others, and in more severe cases, recurrent thoughts of death or suicide.

How Bipolar Disorder Is Diagnosed, and How It's Distinguished from Other Conditions

Diagnosis is based on criteria set out in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5-TR), and it is made by a qualified mental health or healthcare professional, generally through a clinical interview covering the specific pattern, duration, and severity of mood episodes over time. There is no blood test or brain scan that diagnoses bipolar disorder on its own, though a healthcare provider may run tests to rule out a medical condition (such as thyroid disease) that can produce similar symptoms. Because mood symptoms overlap across several conditions, an accurate diagnosis often depends on carefully distinguishing bipolar disorder from other possibilities.

• Major depressive disorder (unipolar depression). Someone with bipolar disorder is often first evaluated or treated during a depressive episode, before any manic or hypomanic episode has occurred or been recognized, which can lead to an initial misdiagnosis of unipolar depression. A careful history — including whether antidepressant treatment ever seemed to trigger unusually elevated or irritable mood — helps distinguish the two.
• Borderline personality disorder. Both conditions can involve intense mood shifts, but the pattern differs: bipolar mood episodes generally last days to weeks and occur somewhat independently of external circumstances, while mood shifts in borderline personality disorder tend to be shorter (hours to a day) and more closely tied to interpersonal triggers and stress.
• ADHD. Some symptoms overlap, including distractibility, restlessness, and impulsivity, but ADHD symptoms are generally persistent from childhood rather than occurring in distinct episodes, and do not typically include the mood elevation, grandiosity, or decreased need for sleep seen in mania or hypomania.
• Substance-induced mood symptoms. Substance use itself can produce manic-like or depressive symptoms, which is part of why a careful evaluation — ideally including a period of sustained abstinence where feasible, and input from people who know the person well — matters for an accurate diagnosis.

What Causes Bipolar Disorder

The exact cause is not fully understood, but research points to a combination of contributing factors rather than any single cause. Bipolar disorder often runs in families, and heredity appears to explain much of that pattern — people with certain genes are more likely to develop the condition, though many genes are involved and no single gene causes it on its own. Genetics alone does not fully explain it either: studies of identical twins have found that one twin can develop bipolar disorder while the other does not, which points to other contributing factors, including differences in brain structure and function, and environmental or life-experience factors that researchers are still working to understand. High-stress life events, major disruptions to sleep patterns, and significant life transitions are commonly reported as triggers for individual episodes, even when they are not considered root causes of the condition itself.

Bipolar Disorder and Substance Use: A Particularly Strong Connection

Among all major psychiatric conditions, bipolar disorder has one of the highest documented rates of co-occurring substance use disorder. Multiple large epidemiological studies conducted over several decades — including the Epidemiologic Catchment Area Study and the National Comorbidity Survey — have consistently found this pattern, with lifetime substance use disorder estimates among people with bipolar I or bipolar II commonly ranging from about 40% to 60%, some individual studies reporting figures even higher. Alcohol and cannabis are the most frequently involved substances, in part simply because they are the most widely available and socially accepted.

Researchers describe the relationship as likely running in both directions. For some people, substance use may represent an attempt to self-manage difficult mood symptoms — using a substance to blunt the agitation of mania or to lift a depressive low. For others, substance use itself may worsen the underlying mood instability, or the two conditions may share some common underlying vulnerability that makes a person more prone to both. Whatever the specific mechanism in an individual case, the two conditions clearly influence each other: co-occurring substance use is associated with more frequent mood episodes, more hospitalizations, and a more complicated overall course for both conditions. There is also a diagnostic complication worth knowing about. Because substance use itself can produce mood symptoms that look like mania, hypomania, or depression, bipolar disorder is sometimes over-diagnosed in people who are actively using substances, when a careful, structured evaluation — often incorporating input from family or others who know the person well — would point to a different explanation. This is part of why an accurate diagnosis usually benefits from evaluation by a professional experienced in working with both conditions.

Treatment Approaches for Bipolar Disorder

Effective treatment for bipolar disorder generally combines medication with psychotherapy and self-management strategies, rather than relying on any single approach alone. Mood stabilizers, including lithium, are typically a core part of treatment, sometimes combined with certain anticonvulsant medications or atypical antipsychotics depending on the specific presentation and symptoms, and occasionally medications targeting sleep or anxiety. Finding the right medication and dosage can take time and often involves some trial and adjustment under a healthcare provider's guidance; stopping medication abruptly or without medical guidance is generally discouraged, since it can trigger a return or worsening of symptoms. Several specific therapy approaches have research support, generally used alongside medication rather than in place of it.

• Cognitive behavioral therapy (CBT) helps identify and change negative thinking and behavior patterns, and teaches coping strategies for managing symptoms and preventing relapse.
• Family-focused therapy involves family members directly, helping the whole household understand the condition, recognize early warning signs of an emerging episode, and improve communication during difficult periods.
• Interpersonal and social rhythm therapy focuses specifically on stabilizing daily routines — sleep and wake times, meal timing, and activity patterns — since disruptions to these rhythms are a well-documented trigger for mood episodes.
• Psychoeducation, often delivered in a group setting, focuses on building a thorough understanding of the condition itself, since research (including NIMH's Systematic Treatment Enhancement Program for Bipolar Disorder, or STEP-BD) has found that people who receive more intensive psychotherapy alongside medication tend to recover faster and stay well longer than those receiving medication alone.

When a substance use disorder is also present, treatment planning typically needs to account for how any medications used for the substance use disorder might interact with mood-stabilizing medications, which is part of why coordinated care between providers treating both conditions matters. Modern treatment approaches generally favor addressing bipolar disorder and a co-occurring substance use disorder together, in a coordinated or integrated way, rather than requiring one to be resolved before starting treatment for the other. Complementary approaches — supplements, specific dietary changes, and similar strategies — are sometimes used alongside standard treatment, but these have not been studied as rigorously as medication and psychotherapy, and should be discussed with a healthcare provider before being added to a treatment plan, rather than substituted for evidence-based treatment.

Living with Bipolar Disorder Day to Day

Because bipolar disorder tends to recur, day-to-day self-management is generally considered as important as formal treatment sessions themselves. This commonly includes keeping a consistent sleep schedule, since sleep disruption is one of the most reliable triggers for both manic and depressive episodes; tracking mood patterns over time (sometimes with a simple daily log) to recognize early warning signs before a full episode develops; managing stress through routines that work for the individual, whether that is exercise, structured downtime, or other strategies; and maintaining consistency with medication and appointments even during periods of feeling well, since stability itself is part of what keeps someone well. Support groups, whether in person or online, connect people managing the same condition and can reduce the isolation that often comes with a chronic mental health diagnosis.

Guidance for Family Members and Loved Ones

Bipolar disorder affects the people around someone, not just the individual diagnosed, and family involvement is often built directly into treatment for that reason. Learning to recognize a person's specific early warning signs — changes in sleep, spending, talkativeness, or irritability that tend to precede an episode — can help a family respond earlier rather than only after a full episode is underway. It is also worth understanding that behavior during a manic or depressive episode reflects the illness, not a deliberate choice, which can help family members respond with less blame and more practical support. Family-focused therapy is specifically designed to help with this, and many communities also have support groups specifically for family members of people with bipolar disorder.

When to Seek Help

Because bipolar disorder is a long-term condition that tends to recur, ongoing management with a healthcare provider is generally part of living with it well, not a one-time fix. If mood symptoms are severe, if there are any thoughts of self-harm or suicide, or if substance use is also a concern, reaching out to a healthcare provider or a mental health professional is a reasonable next step regardless of how far along someone is in understanding what is going on. A primary care provider can also make a referral to a psychiatrist, psychologist, or clinical social worker suited to a specific situation. If you or someone you know is having thoughts of suicide or self-harm, the 988 Suicide & Crisis Lifeline is available 24/7 by calling or texting 988.