Bipolar disorder, characterized by extreme mood swings between manic highs and depressive lows, is often misdiagnosed due to overlapping symptoms with other conditions. Accurate diagnosis requires professional evaluation, but understanding common mimics can reduce stigma and encourage proper care.

1. Borderline Personality Disorder (BPD): BPD features intense mood instability, impulsivity, and fear of abandonment. Unlike bipolar's episodic cycles (lasting days to weeks), BPD moods shift rapidly often within hours triggered by interpersonal stress. Studies, like those in the Journal of Clinical Psychiatry, show up to 20% of BPD cases are initially labeled bipolar.

2. ADHD (Attention-Deficit/Hyperactivity Disorder): Hyperactivity, impulsivity, and distractibility in ADHD mimic manic symptoms. Adults with ADHD may experience "racing thoughts" or risk-taking, but these are chronic rather than cyclical. A 2020 meta-analysis in Psychiatry Research found 1 in 5 bipolar diagnoses in children were actually ADHD.

3. Depression with Agitation or Anxiety Disorders: Major depressive disorder can include irritability or restlessness, mistaken for hypomania. Panic disorder or PTSD may cause hyperarousal resembling mania. Substance-induced mood changes (e.g., from stimulants) further complicate this.

4. Thyroid Disorders or Substance Use: Hyperthyroidism causes agitation and insomnia; hypothyroidism leads to depression. Alcohol, cocaine, or antidepressants can trigger manic-like states. The DSM-5 notes substance/medication-induced bipolar disorder as a key differential.

5. Cyclothymia or Personality Traits: Milder mood fluctuations in cyclothymia are sometimes over-diagnosed as bipolar II.

Misdiagnosis delays treatment lithium helps bipolar but not BPD. If moods disrupt life, consult a psychiatrist for tools like mood charting or the Mood Disorder Questionnaire. Early distinction improves outcomes; bipolar affects 2-3% globally, but mimics are common.