What are mood disorders? Mood disorders, or affective disorders, are mental health problems such as depression, bipolar disorder, and mania. Mood disorders can occur in anyone, including children. The cause of mood disorders is not fully understood, but an imbalance in brain chemicals known as neurotransmitters is likely to play a role. Sometimes mood disorders may be related to a medical condition, substance abuse, life events, or other causes. The most common types of mood disorders include major depression, dysthymic disorder (milder depressive disorder), and bipolar disorder, in which alternating episodes of depression and mania (elevated mood) occur in the same individual. It is normal for your mood to change, and most people go through times of feeling sad. When these feelings last for a very long time or interfere with your life, however, you may have a mood disorder. Symptoms of mood disorders include feelings of sadness, hopelessness, helplessness or inadequacy that do not go away; guilt; suicidal thoughts; fatigue; changes in appetite; irritability; difficulty concentrating; and trouble engaging in daily tasks and relationships. Mood disorders can also cause an elevated mood (mania) that is accompanied by feelings of grandiosity, extreme energy, and heightened arousal. These feelings are stronger and last longer than normal, and interfere with day-to-day life. Treatment for mood disorders depends on the evaluation of a medical professional. Medication, cognitive therapy, behavioral therapy, and lifestyle modification may all be used. It is important to get early treatment for a mood disorder to reduce the severity of symptoms and manage any complications. Seek immediate medical care (call 911) if you, or someone you are with, express suicidal thoughts or attempt to harm yourself or others. Seek prompt medical care if you are being treated for mood disorders and symptoms recur, are persistent, or interfere with your daily life.