People often explain away depression by blaming fatigue or the weather. Depression is a serious disorder caused by the malfunctioning of neurotransmitters in brain neurons. It is easy to check if you are affected by depression with the help of Beck's depression inventory, a popular tool available online on the web. Do your scores show that you have depression? If this is the case, it is necessary to consult with a medical professional and undergo medical tests to confirm the diagnosis and make sure that it is not something else. ## Symptoms of depression - Low mood - Losing interest in things that previously brought you joy - Fatigue that doesn't let you engage — even in your regular routines - Losing faith in yourself and your abilities - Problems concentrating and ===managing daily tasks - Sleepiness and difficulty falling asleep - Eating disorders: decreased appetite or craving for food - Heavy thoughts about death - Uncomfortable bodily feelings: prolonged headaches, back pain, heaviness in the chest (sensation of a stone in the chest or a heavyweight pressing on you) An international classification of disorders suggests paying attention to two main symptoms and three to four additional ones that last longer than two weeks. ## Necessary tests The diagnosis can be confirmed by the following examinations: __Clinical and anamnestic examination__. This includes analysis of symptoms and comparing them with diagnostic criteria. During this examination, a medical professional asks questions about the patient's life and factors that impacted his or her condition. __Pathopsychological research.__ This helps a clinical psychologist give a medical opinion about the patient's emotional-volitional sphere, memory, thinking, and focus to conclude whether it is a depression or another disorder. __Examination by a therapist, neurologist, and endocrinologist.__ This can also be required as symptoms of depression are sometimes related to other disorders. Depression can be a symptom of another illness — for example, hypothyroidism, or be part of many interrelated psychological disorders, such as bipolar affective disorder. __Laboratory methods of examination.__ These are used to identify the cause of the depressive syndrome. Most likely, the patient will be sent for a test of the level of thyroid hormones TSH, free T3, free T4, AT to TPO, and AT to thyroglobulin. It is also advisable to check the level of other hormones (FSH, LH, prolactin, cortisol), have a general blood test and a blood test for serum iron, folic acid, vitamin B12, vitamin D, magnesium, and serotonin. __Instrumental examination methods__. In some cases, an examination requires an electroencephalogram to measure the level of electrical activity in the brain, an electrocardiogram to diagnose arrhythmias or heart block, and computed tomography or magnetic resonance imaging of the brain to exclude a brain tumor. Not all of the above tests are specifically designed for identifying depression. Most of them can exclude the possibility of more serious disorders that have symptoms similar to those of depression and prescribe a proper treatment.