Doctors may need a teenager to take depression-related tests if he is exhibiting symptoms of depression, such as constant fatigue, insomnia, unexplained weight loss and suicidal thoughts, explains the Mayo Clinic. Doctors may require both physical and psychological tests to rule out underlying physical problems.
Teens may be depressed for a variety of reasons, including low social status, poor grades and sexual orientation, says WebMD. If a teen has become withdrawn and isolated, and no longer finds enjoyment in previously enjoyed activities, there is a good chance that he is depressed.
Physical tests, including blood tests, are required to rule out any undetected physical illnesses, such as hyperthyroidism, central nervous system tumors and head trauma, explains WebMD. Doctors may also talk to teens directly about their thoughts and feelings, and may conduct a psychological examination with a questionnaire. To reach the correct diagnosis, doctors ask patients to be as honest as possible during these tests, even if some of the questions are uncomfortable.
There are various types of major depression that teens may have, such as atypical depression, psychotic depression and dysthymia, according to the Mayo Clinic. Symptoms must be severe enough to affect day-to-day activities, and must not be related to other conditions. Other conditions causing symptoms of depression include bipolar disorder, adjustment disorder and schizoaffective disorder.