Bipolar Disorder 

Bipolar disorder is a mental health disorder that brings severe high and low moods, changes in sleep, energy, thinking, and behavior.  People who have bipolar disorder can have periods in which they feel overly happy and energized and other periods of feeling very sad, hopeless, and sluggish.  In between these periods, they usually feel normal.  You can think of the highs and the lows as two "poles" of mood, hence the name "bi" (two) and "polar" (opposite).

Signs

Of Mania ("high" points):

• Excessive happiness, hopefulness, and excitement
• Sudden changes from being joyful to being irritable, angry, and hostile
• Restlessness
• Rapid speech and poor concentration
• Increased energy and less need for sleep
• Showing poor judgement
• Drug and alcohol abuse

Of "Low" points:

• Sadness, feeling of hopelessness
• Loss of energy
• Not enjoying things they once liked
• Uncontrollable crying
• Trouble making decisions
• Irritability
• Excessive need of sleep
• Insomnia
• Appetite changes that make them lose or gain weight
• Thoughts of death or suicide

Credit: Olivia Di Domizio

Treatments:
Medicines: Usually mood stabilizers, and sometimes also antipsychotics or antidepressants.
​Therapy can also help people with bipolar disorder understand it and develop skills to handle it.
https://www.webmd.com/mental-health/borderline-personality-disorder-bipolar-disorder#1​