Tests and diagnosis

By Mayo Clinic Staff

When teen depression is suspected, the doctor will generally do these exams and tests.

  • Physical exam. The doctor may do a physical exam and ask in-depth questions about your teen's health to determine what may be causing depression. In some cases, depression may be linked to an underlying physical health problem.
  • Lab tests. For example, your teen's doctor may do a blood test called a complete blood count or test your teen's thyroid to make sure it's functioning properly.
  • Psychological evaluation. This evaluation will include a discussion with your teen about thoughts, feelings and behavior, and may include a questionnaire. These will help pinpoint a diagnosis and check for related complications.

Diagnostic criteria for depression

To be diagnosed with depression, your teen must meet the symptom criteria in the Diagnostic and Statistical Manual of Mental Disorders (DSM), published by the American Psychiatric Association. This manual is used by mental health providers to diagnose mental conditions and by insurance companies to reimburse for treatment.

Symptoms can be based on your teen's feelings or on the observations of someone else. For a diagnosis of major depression, the following symptoms must occur most of the day, nearly every day, during at least a two-week period, and be a change or worsening in the teen's usual attitude and behavior.

Your teen must have at least one of the following:

  • Depressed mood, such as feeling sad, empty or tearful (in teens, depressed mood can appear as constant irritability)
  • Diminished interest or feeling no pleasure in any or most activities

Your teen must also have four or more of the following:

  • Significant weight loss when not dieting, weight gain, or decrease or increase in appetite (in teens, failure to gain weight as expected can be a sign of depression)
  • Insomnia or increased desire to sleep
  • Restlessness or slowed behavior that can be observed by others
  • Fatigue or loss of energy
  • Feelings of worthlessness, or excessive or inappropriate guilt
  • Trouble making decisions, thinking or concentrating
  • Recurrent thoughts of death or suicide, making a suicide plan or a suicide attempt

To be considered major depression:

  • Symptoms aren't due to a mixed episode, which is mania along with depression that sometimes occurs as a symptom of bipolar disorder
  • Symptoms must be severe enough to cause noticeable problems in day-to-day activities, such as school, social activities or relationships with others
  • Symptoms are not due to the direct effects of something else, such as drug abuse, taking a medication or having a medical condition such as hypothyroidism
  • Symptoms are not caused by grieving, such as temporary sadness after the loss of a loved one

Other types of major depression include:

  • Atypical depression. In this type of depression, key signs and symptoms include increased hunger, weight gain, sleeping a lot, feeling that your arms and legs are heavy, and difficulty maintaining relationships.
  • Postpartum depression. This type of depression can occur in new mothers. It can begin shortly after delivery or even several weeks later. Signs and symptoms are more intense and longer lasting than the baby blues, eventually interfering with the ability to care for the baby and handle other daily tasks.
  • Psychotic depression. This is severe depression accompanied by psychotic symptoms, such as delusions or hallucinations.
  • Dysthymia. Dysthymia (dis-THIE-me-uh) is a less severe, but more long-term form of depression. While it's usually not disabling, dysthymia can prevent your teen from functioning normally in a daily routine and from living life to the fullest.

Other conditions that cause depression symptoms

There are several other conditions with symptoms that can include depression. It's important to get an accurate diagnosis so that your teen gets appropriate treatment. Your doctor or mental health provider's evaluation will help determine if the symptoms of depression are caused by one of the following conditions:

  • Seasonal affective disorder. This type of depression is related to changes in seasons and diminished exposure to sunlight.
  • Adjustment disorder. An adjustment disorder is a severe emotional reaction to a difficult event in your life. It's a type of stress-related mental illness that may affect feelings, thoughts and behavior.
  • Bipolar disorder. Bipolar disorder is characterized by mood swings that range from the highs of mania to the lows of depression. It's sometimes difficult to distinguish between bipolar disorder and depression, but it's important to get an accurate diagnosis because treatment for bipolar disorder is different from that for other types of depression.
  • Cyclothymia. Cyclothymia (sy-kloe-THIE-me-uh), or cyclothymic disorder, is a milder form of bipolar disorder.
  • Schizoaffective disorder. Schizoaffective disorder is a condition in which a person meets the criteria for both schizophrenia and a mood disorder such as depression.
Nov. 07, 2012