The mood spectrum
This guide is for learning, not for diagnosis. Only a clinician who knows your history can tell you which pattern, if any, fits you. Bring your questions from this page to your next appointment.

Bipolar I · Bipolar II · Cyclothymia

Three patterns, one spectrum

All three conditions involve mood moving above and below a person's usual baseline. What sets them apart is how high the highs go, how long each phase lasts, and how much the swings interrupt daily life. This page walks through those differences and what the three have in common.

Mood map

Same shape, different heights

Each line traces a typical course over many months. The grey bands are the clinical thresholds: a mood has to climb above the hypomania line, or fall below the depression line, for long enough to count as an episode. Tap a name to focus on one pattern.

Mood over time for bipolar I, bipolar II, and cyclothymia Bipolar I rises above the mania threshold and falls into depression. Bipolar II reaches hypomania but not mania, then falls into depression. Cyclothymia oscillates in the milder zones without crossing either threshold. Mania Hypomania Milder highs Baseline Milder lows Depression Time →
Bipolar IAt least one full manic episode. Depression is common but is not required for the diagnosis.
Bipolar IIHypomania plus at least one major depressive episode. Never a full manic episode.
CyclothymiaMany ups and downs over at least two years that never reach a full episode in either direction.

How long is "long enough"?

Duration is part of the definition. These are the minimums clinicians use; real episodes are often longer.

Hypomanic episode
4+ days
Manic episode
7+ days*
*Any length counts if hospital care is needed.
Major depressive episode
14+ days
Cyclothymic pattern
2+ years†
†One year for children and teens; symptoms present at least half the time with no symptom-free stretch longer than two months.

*Any length counts if hospital care is needed. †One year for children and teens; symptoms present at least half the time with no symptom-free stretch longer than two months. Bars are not to scale.

Show to scale
Logarithmic scale: 4 days → 2 years

Building blocks

The episodes that make up each pattern

Diagnoses are built from a small set of episode types. Learn these four and the differences between the three conditions become easy to see.

  • Mood that is unusually elevated, expansive, or irritable, with a clear jump in energy
  • Much less need for sleep, yet still energetic
  • Racing thoughts, rapid or pressured speech
  • Grand ideas or inflated confidence
  • Risky decisions with money, driving, sex, or plans
  • Severe enough to clearly disrupt work or relationships, or to require hospital care; may include losing touch with reality
Appears in:
I
II
Cyc
  • The same kinds of changes as mania, but milder
  • Noticeable to people who know you well
  • Does not cause major disruption or need hospital care
  • Never includes losing touch with reality
  • Often feels productive or pleasant, which makes it easy to miss or to describe as "just a good week"
Appears in:
I
II
Cyc
  • Low mood or loss of interest in nearly everything
  • Changes in sleep, appetite, or energy
  • Trouble concentrating or making decisions
  • Feeling worthless or guilty
  • Moving or thinking noticeably slower, or feeling restless
  • Thoughts that life is not worth living
Appears in:
I
II
Cyc
  • Periods with some hypomanic-type symptoms that don't add up to a hypomanic episode
  • Periods with some depressive symptoms that don't add up to a major depressive episode
  • Present much of the time over years
  • The defining feature of cyclothymia, but also common between episodes in bipolar I and II
Appears in:
I
II
Cyc

Side by side

What each diagnosis requires

Compare two

Bipolar I

Defined by mania · ICD-11 6A60 "Bipolar type I disorder"

Must have
At least one manic episode.
Usually also has
Major depressive episodes, often longer and more frequent than the manic ones. Hypomania may occur too.
Highest point
Mania: marked impairment, possible hospitalization, possible psychosis.
What it can look like
A sudden stretch of not sleeping, big plans, spending, and speed, followed weeks or months later by a heavy, slowed-down low.

Bipolar II

Defined by hypomania plus depression · ICD-11 6A61 "Bipolar type II disorder"

Must have
At least one hypomanic episode and at least one major depressive episode.
Must never have
A full manic episode. If one ever occurs, the diagnosis changes to bipolar I.
Highest point
Hypomania: a clear change, but no major disruption and no psychosis.
What it can look like
Long, recurring depressions that are the main problem, with lighter "up" weeks that may have felt like good times rather than symptoms.

Cyclothymia

Defined by a persistent, milder pattern · ICD-11 6A62 "Cyclothymic disorder"

Must have
Two or more years of many periods with hypomanic symptoms and many periods with depressive symptoms, present at least half the time.
Must never have
A manic, hypomanic, or major depressive episode during that time. Any of those changes the diagnosis.
Highest point
Milder highs that stay below the hypomania line.
What it can look like
Being described as "moody" for years; rarely feeling level for more than a couple of months; ups and downs that are real but never quite become an episode.
Comparison of bipolar I, bipolar II, and cyclothymia
Feature Bipolar I Bipolar II Cyclothymia
Full mania Required (at least once) Never Never
Hypomania May occur Required (at least once) Symptoms only, never a full episode
Major depression Common, not required Required (at least once) Symptoms only, never a full episode
Time frame One episode is enough One of each is enough At least two years of the pattern
Psychosis possible Yes, during mania or severe depression Only during depression, never during hypomania No
Hospital care Sometimes needed during mania Sometimes during depression Rare
Time between episodes Can be fully level; milder swings are common Can be fully level; milder swings are common Rarely level for more than two months
Can it change over time? Diagnosis stays bipolar I Becomes bipolar I if mania ever occurs Can develop into bipolar I or II for some people
ICD-11 code 6A60 6A61 6A62
ICD-11 wording At least one manic or mixed episode At least one hypomanic episode and at least one depressive episode; no manic or mixed episode At least two years of unstable mood with many hypomanic and depressive periods; no manic, mixed, or full depressive episode

Two rulebooks, one picture

Clinicians use one of two diagnostic systems: the DSM-5-TR, common in the United States, and the ICD-11, used by the World Health Organization and most of the world. They agree on the shape of all three conditions. The differences are in the fine print:

  • Mixed episodes. ICD-11 keeps "mixed episode" (high and low symptoms at the same time) as its own episode type, and a mixed episode counts toward bipolar I. DSM-5-TR describes the same thing as a manic or depressive episode "with mixed features."
  • Hypomania duration. DSM-5-TR sets a minimum of four days. ICD-11 says "several days" and leaves the exact number to clinical judgment.
  • Cyclothymia's highs. In DSM-5-TR the ups must stay below the hypomania line. ICD-11 allows some of them to reach a full hypomanic episode, as long as there has never been a manic, mixed, or full depressive episode.
  • Names. ICD-11 says "bipolar type I" and "bipolar type II"; DSM-5-TR says "bipolar I" and "bipolar II." Same conditions.

In common

Where the three overlap

They are all cyclicalMood moves away from baseline in both directions and comes back. The pattern, not any single bad or good day, is what matters.
They are all biological and treatableNone of them is a personality flaw or a failure of willpower. Medication, therapy, and routine each have strong evidence.
Sleep is a lever for all threeLost sleep can trigger an upswing and is often the first warning sign. Protecting a regular sleep schedule is a treatment in itself.
The lows are usually the heaviest partAcross all three, people spend far more time below baseline than above it, and the lows are typically what brings someone to care.
Early signs are learnableEach person tends to have a recognizable "signature" before a shift: less sleep, more spending, more irritability, or pulling away. Knowing yours gives you time to act.
They sit on one spectrumThe boundaries are useful for choosing treatment, but they are lines drawn across a continuum. Diagnoses can be revised as more is learned about your history.

Common misunderstandings

Myth and reality

Often heard"Bipolar II is the mild version, so it isn't serious."
Closer to the truthThe highs are milder. The depressions are not, and they often last longer than in bipolar I. Bipolar II carries real risk and deserves real treatment.
Often heard"Bipolar means your mood changes every few hours."
Closer to the truthEpisodes are measured in days, weeks, and months. Hour-to-hour shifts usually point to something else, or to a very stressful period, and are worth discussing with your clinician.
Often heard"Cyclothymia isn't a real diagnosis, it's just being moody."
Closer to the truthIt is a defined condition with a required duration and pattern. It can affect relationships and work, and it can progress, which is why it is worth identifying and treating.
Often heard"If I feel great and productive, that can't be a symptom."
Closer to the truthHypomania often feels good. The tell is that it is a change from your usual self that other people notice, and that it tends to be followed by a fall.

Check your understanding

Five quick questions

This checks what you learned on this page. It is not a screening tool and cannot tell you whether you have any of these conditions.

Support

Questions worth bringing to your next session

Understanding your own pattern is one of the most useful things you can do. These prompts can help start that conversation.

If you are having thoughts of ending your life, or you are worried about your safety, contact your clinician, go to the nearest emergency department, or call or text your local crisis line now. In the United States, call or text 988.

Glossary

Words you'll hear

Baseline (euthymia)
Your usual, level mood when you are not in an episode.
Episode
A stretch of mood change that meets a defined threshold for symptoms and duration.
Mania
A high, energized state lasting a week or more that clearly disrupts life.
Hypomania
A milder high lasting at least four days that others notice but that does not cause major disruption.
Major depressive episode
Two or more weeks of low mood or lost interest with several other symptoms.
Mixed features / mixed episode
Symptoms of both poles at the same time, such as racing thoughts with a low mood. ICD-11 treats this as its own episode type; DSM-5-TR adds it as a specifier.
Rapid cycling
Four or more episodes in a single year.
Psychosis
Losing touch with reality, such as fixed false beliefs or hearing things others do not.
Mood stabilizer
A class of medication that reduces the size and frequency of mood swings.
Relapse signature
Your personal set of early warning signs before an episode.