A disturbance in the prevailing psychological state of an individual is termed as a mood disorder. It is characterized by a disturbance in the person's emotional state and manifests itself in different forms. Mood disturbances may include depression, mania, or a combination of these. Mood disorders are classified as depressive, bipolar, and substance-induced. Depressive and bipolar disorders are further classified into certain types of depressions, while substance-induced disorders are categorized on the basis of the chemical substance causing the condition. Major depressive disorder is characterized by severe depressed mood, loss of happiness and hope, coupled with feeling worthless, guilty, empty, and nervous. The individual may experience loss of or increased appetite, and problems with concentration, memory, and decision-making. Suicidal tendencies may also be seen. Experiencing these symptoms together is termed as a major depressive episode. A state of depression, which is not coupled with feelings of mania is known as unipolar depression, while in the presence of mania, the condition is called bipolar. These depressive disorders can be further classified as follows. Atypical depression: In this type, an individual experiences weight gain due to increased appetite, excessive sleep, and heaviness in the limbs. He becomes hypersensitive to rejection and experiences a disturbed social life. Catatonic depression: It is a severe major depressive disorder that is characterized by disturbed motor abilities. Those affected by catatonic depression may experience bizarre body movements or periods of total immobility. Melancholic depression: It is characterized by loss of pleasure in the activities of daily life, feelings of guilt and grief of loss. Those with melancholic depression also experience excessive loss in weight. The symptoms may worsen in the early morning hours. Minor depression: If the symptoms persist for a minimum of two weeks, but do not meet the criteria for the depression to be classified as major, the condition is termed as minor depressive disorder. Dysthymia: The symptoms are similar to those experienced in unipolar depression, though less severe and lasting longer. They include changes in appetite, changed sleep patterns, fatigue, low self-esteem, and difficulty concentrating. Double depression: It is characterized by depressed mood that persists for a minimum of two years. Episodes of major depression are seen intermittently. Postpartum depression: It is experienced by females post delivering a baby. Usually, the symptoms are seen within three months of labor and may last for three months. Psychotic depression: It is characterized by delusions and hallucinations. The delusions often correspond with the contents of the depressing themes. Recurrent brief depression: It is different from major depressive disorders in terms of the duration for which it persists. The depressive episodes in patients of recurrent brief depression occur about once a month and last for two or three days. Seasonal affective disorder: This, as the name suggests, is characterized by a seasonal pattern, which is to say, those affected experience symptoms of depression during the winter season. These depressive feelings can be attributed to lack of exposure to sunlight during winter. Depressive Disorder Not Otherwise Specified: When the symptoms are seen but do not fit the diagnostic criteria for any specific disorder, the condition is referred to as Depressive Disorder Not Otherwise Specified or DD-NOS. It is a mood disorder that manifests itself in the form of alternating periods of depression and mania. There are changes in an individual's mood and behavior switching between an overexcited state called manic and a state of feeling hopeless called depressive. If the symptoms are a mix of those experienced in the manic and depressive states, the state is called mixed. Bipolar disorder is relatively less common, but it is also said that it often goes undiagnosed. Mostly, bipolar disorder develops in the late teen years or during early adulthood. In children, it is known as early-onset bipolar disorder. In them, changes in mood and other symptoms are seen more frequently than in adults with bipolar disorder. Bipolar I is characterized by a history of manic episodes with or without the presence of depressive episodes. Bipolar II is characterized by intermittent episodes of mania and depression. Depression may alternate with hypomanic episodes in which the symptoms of mania are milder; that is, they are observable but do not impair one's functioning. Cyclothymia consists of hypomanic episodes accompanied by milder mood disturbances. Full manic or major depressive episodes are not seen. Bipolar Disorder Not Otherwise Specified is when an individual shows some symptoms of bipolar disorder but the condition does not meet the diagnostic criteria for any particular type of bipolar disorder. As the name suggests, these mood disorders are those caused by a chemical substance or drug that affects one's psychological state. Addiction to a substance or withdrawal from it can affect mood levels and the individuals may have manic or depressive episodes. Alcohol-induced: Research suggests that heavy drinkers may experience depression. Suicidal tendencies may also be seen. Moderate to heavy drinkers may experience euphoria, fluctuations in mood, feeling high, and reduced control on impulses. In case of addiction to alcohol coupled with excessive mental stress, the individual may resort to violence. Withdrawal from alcohol causes fatigue, sleeplessness, decreased interest in sex, and unstable mood. Caffeine-induced: If consumed in excess, caffeine may lead to anxiety and even panic attacks in some cases. Nicotine-induced: Nicotine dependence can give rise to feelings of depression. Nicotine withdrawal also has similar symptoms. Due to Nervous System Stimulants: The intoxication of such substances leads to problems with concentration and attention. Reduced mental function may be seen. Their withdrawal symptoms include depression and fatigue. A long-term use of stimulants like amphetamine affects the brain, leading to long-term difficulties in concentration and memory. Mood disorders due to the use of these stimulants and alcohol may show symptoms similar to those of bipolar disorder. Due to Opioids: Opioids lead to feelings of euphoria. Their long-term use leads to depression. Withdrawal from these leads to body aches and agitation. The withdrawal symptoms may also include anxiety, depression, and disturbed sleep. Due to Sedatives: The symptoms are similar to those in alcohol-induced mood disorders. Withdrawal from sedatives leads to feelings of anxiety, depression, and disturbed sleep. In severe cases, hallucinations may be experienced. Due to Hallucinogens: Individuals using these, experience delusions and hallucinations. Psychotic reactions and depression may also be seen. A mood disorder can be diagnosed as one occurring due to a general medical condition, when it can be concluded that its symptoms are a result of the psychological impact of the medical condition, and not just a physiological response to it. Diseases of the endocrine system, Parkinson's disease, nervous system disorders, and cardiovascular diseases can lead to mood disorders. Very painful or incurable diseases lead to feelings of depression in those affected. Some patients may show suicidal tendencies. A mood disorder that does not meet the criteria for any specific disorder can be classified as Mood disorder not otherwise specified or MD-NOS. A combination of mood and anxiety disorder or minor depression can be classified as MD-NOS. Mood disorders are exhibited in terms of a change in behavior and episodes of depression, anxiety, and agitation. People with mood disorders show an unusual and sudden change in their behavior and go through periods of depression or over-excitement. They experience feelings of irritability and sadness. Some mood disorders are characterized by loss of appetite leading to weight loss, while overeating leading to weight gain is experienced in others. Imbalances in the neurotransmitters are believed to be among the causes of mood disorders, mainly depression and bipolar. Hormonal imbalances can lead to depression. Excessive mental stress or difficulty coping with it can also cause mood disorders. It is also known that these disorders can run in families in the form of certain genetic traits. For example, bipolar mood disorder is genetically transmitted. Depressive symptoms may result from adjustment disorders. A stressful event such as a failure, a problem in the family, a relationship issue, among others may lead to depression that lasts for a few months and goes away after the stressor is removed. The condition cannot be classified as a major depressive disorder. More severe than premenstrual syndrome, PMDD affects 3% to 8% women during their reproductive years. Symptoms include, low energy levels, fatigue, lost interest in daily activities, feelings of despair, anxiety, and irritability. Disturbed eating and sleep patterns may also be seen. Its classification as a mental disorder is relatively recent. Seen in children, it is characterized by frequent temper tantrums, persistent irritability, and overreactions, and affects the social life of an individual. For the disorder to be classified as DMDD, the symptoms need to have begun before the age of 10 and should have lasted for at least one year. ➺ Studies have shown that atypical depression is about four times more common in females than in males. ➺ Depression, bipolar disorder, and cyclothymic disorder are the most common mood disorders. ➺ It is observed that mood disorders in children and teenagers are among the most under-diagnosed mental health problems. ➺ Studies show that catatonia is most seen in elderly patients with severe depression. ➺ A child is more likely to have a mood disorder if one or both his parents have it. If a mother passes a mood disorder trait to her children, a girl child is more prone to have a disorder. If a father passes the trait, his son is more likely to have a mood disorder. ➺ Siblings and close relatives of people with mood disorders, have higher chances of getting the disorder. ➺ According to the World Health Organization, major depressive disorder is the main cause of disability in the Americans aged between 15 and 44. ➺ According to the Canadian Mental Health Association (CMHA), there is a higher probability of women being affected by depression, dysthymic disorder, and seasonal affective disorder. Bipolar disorder can affect both males and females equally. ➺ An article on the CMHA website says that about 3.5% children and 3-7% teenagers are diagnosed with depression, and in many cases, bipolar disorder is detected between the age of 15 and 19. ➺ A report from Mental Health America says that about 20% people in the United States experience at least one depressive symptom in a month and 12% of the US population reports two or more depressive symptoms in a year. Mood disorders need immediate help. Identification of the health condition as a mood disorder and the correct diagnosis are of utmost importance when it comes to administering the right treatment. The treatment depends on the physical and mental state of the patient and the external factors influencing his well-being. Treatment measures include antidepressant medicines (for depression), mood stabilizers (for bipolar disorder), and psychological aid. Cognitive behavioral therapy is commonly used to treat mood disorders. It helps the patient know how his mood affects his thoughts and behavior, and also helps him combat the problem. Interpersonal therapy can help the patient improve social interactions. In cases where counseling or medications do not help, electroconvulsive therapy can be given. Support from family and friends plays a crucial role in helping a patient cope with his mood disorder. But perhaps, self-help through a proper diet, regular exercise, adequate sleep, socialization, and managing stress is the best help in managing mood problems.