Depression is a serious issues that affects thousands, if not millions, of people. While most people think of depression as a state of sadness, the side effects of depression can be just as debilitating as the sadness and less likely to be associated with the condition.InsomniaDepression does not affect everyone the same way, but one of the most common signs that a person is depressed in a change in sleep patterns. While some people just cannot get enough sleep, more commonly insomnia ensues. insomnia covers both the inability to fall asleep and the inability to stay asleep. The change in sleep habits lead to other side effects that can affect how a person works and interacts with the people around them. For example, the person may have no energy, become cranky and lack of focus or concentration.Weight ChangesSudden weight changes may be a sign of depression. Most commonly, depression sufferers gain weight. The weight changes can be attributed to the stress and desperation of the depressed state, along with the lack of energy to exercise and changes in eating habits retarding the metabolism.AddictionIn an effort to dull the pain, depressed individuals often turn to drugs and alcohol, which only intensifies the problem, including the added side effects of tremors, hiding their addiction, increased personal relationship problems, memory loss.UntreatedIf depression is not treated, the side effects will not likely to just disappear. In fact, they can intensify to the point that the afflicted person becomes danger to himself or others. He may start participating in harmful activities, such as self-mutilation, and accelerate to suicide. While no one can force an adult to seek help, friends and family should remain on alert and call local authorities of the depressed individual becomes a threat to himself or others. Do not wait until something serious happens.Depression can be a serious mental condition that can affect every part of a person's life, and over time, the mental condition can manifest itself into serious physical problems, such as coronary artery disease and heart attacks. With proper treatment, the condition can be managed, and a person can lead a normal life. Without treatment, life can be a misery existence.