Mood Swings:

Mood swings — the telltale symptom of bipolar disorder — are sudden or intense changes in one’s emotional state, changing unexpectedly from being okay/calm to being depressed, irritable, or angry. Mood swings are often accompanied by changes in sleep and eating patterns and can last for hours, days, weeks, and even months — severely disrupting daily life. Occasional, mild-to-moderate mood shifts in response to daily life are normal. When severe, frequent, long-lasting, and interfering with daily functioning, relationships, or work, they may be a symptom of an underlying physical or mental health condition that requires medical attention, including:

• Hormonal changes are a common cause, particularly during puberty, the menstrual cycle (PMS and PMDD), pregnancy, and menopause.
• Lifestyle factors, including not getting enough quality sleep (making it harder to process emotions and regulate mood), diet (blood sugar peaks/valleys from an unhealthy diet or skipping meals can lead to emotional ups and downs), high stress levels, and alcohol and drug use, or withdrawal (can affect brain chemistry and lead to erratic emotions).
• Medical conditions can cause mood swings, either directly or by triggering anxiety or depression (thyroid disorders, diabetes, epilepsy, Parkinson’s, multiple sclerosis).
• Mental health conditions: Severe or persistent mood swings can be a symptom of a mental health condition. These include: bipolar disorder between extreme emotional highs (mania or hypomania) and lows (depression), borderline personality disorder (BPD) with frequent, intense, and rapid mood shifts, often in response to interpersonal interactions.
• Depression, though associated with persistent sadness, can involve mood swings, including irritability or anger outbursts.
• Anxiety disorders or ADHD can also affect emotional regulation and lead to mood instability.