What Is Bipolar I Disorder

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Bipolar I disorder is a mood disorder defined by at least one manic episode, a distinct period of abnormally elevated, expansive, or irritable mood with increased energy, lasting at least a week or severe enough to require hospital care. Most people with bipolar I also experience depressive episodes, although these are not required for the diagnosis. Bipolar I is a lifelong condition, but with treatment many people live stable, full lives. It is different from bipolar II, which involves hypomania, a milder form of elevated mood, rather than full mania.

What Bipolar I Looks Like

During a manic episode, people may experience:

• Elevated, euphoric, or intensely irritable mood.
• Greatly reduced need for sleep, sometimes feeling rested after only a few hours, as described on the page about barely sleeping and feeling unstoppable.
• Racing thoughts, rapid speech, and jumping between ideas.
• Inflated self-esteem or grandiose beliefs.
• Taking on many projects at once, or risky behaviour such as spending sprees or impulsive decisions.
• In severe cases, psychotic symptoms such as delusions or hallucinations.

Depressive episodes bring low mood, loss of interest, fatigue, changes in sleep and appetite, and sometimes thoughts of suicide. Between episodes, many people return to their usual functioning. Manic episodes often strain relationships, work, and finances, and people may not recognize their own changes at first.

Why It Happens

Bipolar I has a strong genetic component and tends to run in families. Differences in brain systems that regulate mood, sleep, and energy are involved. Episodes can be triggered by sleep disruption, major stress, substance use, and certain medications, including antidepressants taken without a mood stabilizer. Onset is often in the late teens or twenties, though it can begin at other ages. Bipolar I is not caused by personality or weakness.

A key challenge in bipolar I is that insight can change during episodes. At the start of mania, people often feel better than ever, more confident and productive, and may not want to slow down or see a doctor. Loved ones are often the first to notice warning signs, such as sleeping far less, talking faster, or unusual spending. Agreeing on a plan during stable periods, including who to call and which early signs to watch for, can make a big difference later.

What It Is Not

• Not ordinary mood swings. Manic episodes are sustained, marked changes lasting days or longer, not shifts within an afternoon. The page on dramatic mood swings explains the difference.
• Not bipolar II. Bipolar II involves hypomania, which is less severe and does not cause psychosis or require hospitalization.
• Not ADHD. ADHD involves lifelong attention and activity differences, while bipolar symptoms come in episodes.
• Not borderline personality disorder. BPD mood changes are usually brief and triggered by relationships, while bipolar episodes last longer.
• Not a substance-induced state alone. Stimulants and other substances can cause mania-like symptoms, which need careful assessment.

How It Is Assessed and Treated

Bipolar I is diagnosed by a physician or psychiatrist, often with input from a psychologist, through a detailed history of mood episodes, sleep, family history, and input from loved ones. Treatment centres on mood-stabilizing medication prescribed and monitored by a physician or psychiatrist. Psychological treatments add important support: psychoeducation, mood tracking, stable routines for sleep and activity, relapse prevention planning, and family involvement. Therapies such as cognitive behavioural therapy and interpersonal and social rhythm therapy can reduce relapse and improve quality of life. Avoiding alcohol and recreational drugs also supports stability.

Getting Support at Pacific Maple Psych Centre

If you are living with bipolar I, or wondering whether your mood episodes fit it, a psychological assessment can help clarify the pattern, and therapy can support stability, routines, and relapse prevention alongside your medical care.