Some examples of mood disorders include:
Major depression. This condition is characterized by the patient lacking energy, losing interest in regular activities, and lacking focus for about two weeks. Major depression mostly affects premenopausal women.
Chronic depression or dysthymia. This is a low-grade form of depression or chronically irritable mood that can last for up to two years.
Bipolar disorder: This is a condition where the patient alternates between moments of sadness or depression and periods of excitement or mania.
Substance-induced mood disorders. These are mood disorders caused by medication, alcoholism, drug abuse, and exposure to toxins.
Mood disorders caused by illness. Several medical conditions such as cancer, infections, injuries, and chronic illnesses can cause mood swings.