Everyone gets sad sometimes, and may even say they feel depressed, but true clinical depression is not a simple matter of fleeting emotions. According to the Depression and Bipolar Support Alliance, "Depression is a treatable medical illness involving an imbalance of brain chemicals called neurotransmitters and neuropeptides." Episodes of depression are common among mood disorders, such as postpartum depression, bipolar disorder or seasonal affective disorder. While the symptoms are different for each person, there are some common signs to look for; if they persist or are overwhelmingly strong, it's time to find help.
Sadness
A constant feeling of overwhelming sadness is one of depression's most common symptoms, according to the National Institute of Mental Health (NIMH). This can take the form of an empty feeling, pessimism, indifference, hopelessness, worthlessness, self-loathing or guilt. A depressed person might lose interest in hobbies or activities he used to enjoy or withdraw socially, because he feels unable to experience joy anymore. Attempts to control negative thoughts don't work, and it becomes difficult to function. Often crying spells will occur for no explainable reason, and thoughts of death or suicide can recur.
Anger or Irritability
Some people with depression become angry, irritable or more short-tempered than they usually are. Everything seems to grate on their nerves. They may also be restless, agitated, worried or feel intense anxiety, as if they are in danger. Depressed people with these symptoms may feel they can't relax or sit still for more than a few moments, so they're never at peace. Men in particular may lash out at people around them, according to the NIMH, or get angry at themselves for not being able to shake off the depression on their own.
Pain
Depressed people may get persistent unexplained pains or other physical symptoms that are the result of tension, stress and fatigue. This might be constant headaches, stomachaches, indigestion, difficulty breathing, tightness of the chest, back pain or aching muscles.
Sleep Pattern or Appetite Changes
Sleeping pattern changes might manifest as insomnia, early waking or oversleeping and can lead to fatigue, exhaustion, lethargy and loss of energy. When this happens, it becomes difficult to concentrate, remember things or complete tasks, so it can be overwhelming just to make it through the day. Changes in appetite can take the form of not being able to eat or not being able to stop eating, which can lead to a gain or loss of more than 5 percent body weight in a single month.
