unipolar disorder
major depression
A mental disorder characterised by severe depression lasting essentially without remission for at least two weeks, with symptoms that interfere with the ability to work, sleep, eat and enjoy once-pleasurable activities.Clinical findings
Feelings of guilt, hopelessness, all-encompassing low mood accompanied by low self-esteem, persistent thoughts of death or suicide; difficulties in concentration, memory and decision-making capacity, behaviour (changes in sleep patterns, appetite, weight), physical well-being; persistent symptoms (e.g., headaches or digestive disorders) that do not respond to treatment; disabling episodic major depression can occur several times in a lifetime.
Patient discussion about unipolar disorder
Q. Bipolar depression And Unipolar depression Is bipolar depression different from unipolar depression?
The treatment is also quite different (lithium and stabilizers for bipolar, SSRI for depression)
You may read more here:
www.nlm.nih.gov/medlineplus/bipolardisorder.html