Bipolar disorder is not an anxiety disorder. They are separate conditions in different diagnostic categories. Bipolar disorder is classified as a mood disorder, defined by episodes of mania or hypomania (abnormally elevated mood and energy) alternating with periods of depression. Anxiety disorders, by contrast, are defined by excessive fear, worry, or dread that persists without the mood cycling that characterizes bipolar disorder.
The confusion is understandable, though. The two conditions overlap in significant ways, and roughly 40% of people with bipolar disorder also have a diagnosable anxiety disorder. That overlap leads to frequent misdiagnosis and complicates treatment.
How Bipolar Disorder Is Classified
The DSM-5, the standard diagnostic manual used in psychiatry, places bipolar disorder in a category called “Bipolar and Related Disorders,” separate from the “Anxiety Disorders” category. Bipolar I disorder requires at least one manic episode, a period of persistently elevated, expansive, or irritable mood with increased energy that causes significant impairment or requires hospitalization. Bipolar II involves hypomanic episodes (a less severe form of mania) paired with major depressive episodes.
Anxiety disorders include conditions like generalized anxiety disorder, panic disorder, social anxiety disorder, and specific phobias. What unites them is persistent, excessive worry or fear that isn’t tied to mood cycling. A person with generalized anxiety disorder, for example, experiences ongoing worry across many areas of life without the distinct “up” and “down” mood episodes that define bipolar disorder.
Why the Two Get Confused
Several bipolar symptoms look a lot like anxiety. During manic episodes, people often feel restless, keyed up, and unable to concentrate. Their thoughts race. They may feel a sense of dread or loss of control. These experiences mirror what someone with an anxiety disorder feels, and the DSM-5 even includes an “anxious distress” specifier that clinicians can add to a bipolar diagnosis when symptoms like feeling tense, restless, or unable to concentrate are prominent.
During depressive episodes, anxiety symptoms are even more common. Research has found that the level of anxiety someone experiences during a bipolar depressive episode predicts how long and how severe that depression will be. Physical symptoms of anxiety (muscle tension, racing heart, stomach distress) and psychological anxiety (excessive worry, apprehension) during depressive episodes are both tied to worse outcomes over time.
This symptom overlap creates a real diagnostic problem. In one primary care study, 92.7% of patients who met full criteria for bipolar disorder were not correctly diagnosed by their physician. Only 7 out of 96 patients with bipolar disorder received the right diagnosis. In many of these cases, the anxiety symptoms were what patients reported most visibly, leading to an anxiety disorder label while the underlying bipolar condition went unrecognized.
How Often Anxiety and Bipolar Disorder Occur Together
About 40.5% of people with bipolar disorder will meet criteria for an anxiety disorder at some point in their lives. At any given time, roughly 38% have a current anxiety disorder. These numbers are remarkably high and help explain why the two conditions are so often conflated.
The most common anxiety disorders in people with bipolar disorder break down as follows over a lifetime: panic disorder at 18.1%, social anxiety disorder at 13.5%, generalized anxiety disorder at 13.3%, and OCD at 9.7%. These rates are similar whether someone has bipolar I or bipolar II, though bipolar II shows slightly higher rates of current anxiety across most subtypes.
When anxiety and bipolar disorder co-occur, the picture gets more serious. People with both conditions tend to develop their first depressive episode earlier in life, experience a higher total number of depressive episodes, and face a greater risk of suicide attempts compared to people with bipolar disorder alone. OCD and panic disorder, when present alongside bipolar disorder, are associated with the most severe clinical outcomes. OCD co-occurring with bipolar disorder is linked to the earliest age of onset and the highest number of depressive episodes.
What’s Different in the Brain
Bipolar disorder and anxiety disorders involve overlapping but distinct patterns of brain activity. In bipolar disorder, the areas of the brain responsible for cognitive control and decision-making (particularly the prefrontal cortex) show reduced activity, while areas involved in emotional processing, especially the amygdala, are overactive. During mania, the prefrontal cortex is underactive compared to healthy individuals. During bipolar depression, the amygdala responds more intensely to negative emotional cues than it does during mania or in people without the condition.
Bipolar disorder also involves changes in the brain’s immune cells, which appear to be overactive, and elevated levels of certain signaling chemicals in deep brain structures. These patterns are distinct from what’s typically seen in primary anxiety disorders, where the threat-detection system is chronically overactive but the dramatic cycling between emotional states doesn’t occur.
Why Getting the Distinction Right Matters for Treatment
This isn’t just an academic distinction. Getting the diagnosis wrong can lead to treatment that makes things worse. The standard first-line medications for anxiety disorders, particularly SSRIs (a common class of antidepressant), carry a real risk of triggering mania in someone with undiagnosed bipolar disorder. Research using electronic health records found that SSRIs were associated with a 34% increased risk of developing mania or a bipolar diagnosis. Another commonly prescribed antidepressant, venlafaxine, showed a 35% increased risk. Across all types of antidepressants studied, rates of new mania ranged from about 13 to 19 cases per 1,000 people treated per year.
This means that if someone’s anxiety is actually part of an underlying bipolar disorder, treating it with antidepressants alone could destabilize their mood and trigger a manic episode. Bipolar disorder is primarily managed with mood stabilizers and certain antipsychotics, which form the foundation of treatment. Anxiety symptoms that exist within the context of bipolar disorder often improve when the mood disorder itself is properly controlled.
If you experience both significant anxiety and episodes of unusually high energy, decreased need for sleep, impulsive behavior, or dramatic mood shifts, it’s worth raising the possibility of bipolar disorder with a mental health professional rather than accepting an anxiety diagnosis at face value. Given that nearly half of bipolar cases go unrecognized even when a clinician is aware something is wrong, being an informed participant in the diagnostic process matters.