Bipolar disorder is a mental illness that causes people to have extreme mood swings. These mood swings can go from very high (mania) to very low (depression).


People with bipolar disorder may experience different symptoms during mania and depression. Bipolar disorder was previously known as Manic Depression/Manic Disorder. 
During mania, people may experiences extremes of the following:
Euphoria (manic phase) 
Excitement
Increased energy levels
Talkative - often grandiose and delusional in context
Reckless, impulsive and high risk behaviour
Irritability 
Insomnia - reduced physical need for sleep, this will be prolonged more than what can be expected 
Overactive - as if on overdrive (psychomotor agitation)
Disorganized and distracted easily
Spendthrift - extreme spending more than normal, often high end goods and things that could, as a result, present the person with serious negative financial consequences.
Have racing thoughts
Some people with Bipolar can experience what is termed as mixed features, where they have mixed episodes of mania and depression at the same time.   

Major Depressive Episode: 
To be diagnosed with a major depressive episode, the DSM-5 states that an individual must experience five or more of the following symptoms in two weeks: 

Sad - depressed mood for the majority of the day on a daily basis
Feelings of hopelessness, low self-esteem and feeling worthless
Fatigued - significant loss of energy
Loss of interest in activities they used to enjoy
Difficulty concentrating and ability to think
Changes in appetite - weight loss, decreased appetite or, the opposite 
Difficulty sleeping, pacing the room
Recurring intrusive thoughts of dying or suicide, or suicide attempt 

Bipolar disorder is a serious and lifelong mental health disorder, but it can be treated and managed successfully. 
Treatment usually includes medication and therapy. Medication helps to stabilize mood swings, and therapy empowers people to learn how to manage their symptoms.