Depression can be triggered by other mental illnesses, but it can also lead to certain mental illnesses. These include anxiety disorders, schizophrenia, eating disorders, and substance abuse. Together, these conditions affect millions of Americans each year. Fortunately, they can be treated effectively -- allowing those affected to lead normal and productive lives.

Anxiety Disorders

Anxiety disorders produce an intense, often unrealistic and excessive state of apprehension and fear. They can occur during a given situation, or in anticipation of a particular situation occurring. When anxiety strikes, a person's blood pressure may rise, his or her heart races, and breathing becomes more rapid. The person may also feel nauseated and experience other signs of agitation and discomfort. The causes of anxiety are as individual as the people affected, and the symptoms vary widely in degree.

Anxiety disorders will affect close to 25 million people at some time in their lives, affecting women twice as frequently as they affect men. Some of the most common anxiety disorders are: Panic disorder, social phobia, agoraphobia, posttraumatic stress disorder, and obsessive-compulsive disorder.

Generalized Anxiety Disorder

Generalized anxiety disorder is defined as a period of uncontrolled worry, nervousness and anxiety for six months or more. The anxiety may initially focus on a specific worry (relationships, career, or finances, for example), or may present as a vague anxiety about almost anything. Accompanying irritability is very common. Physical symptoms often develop, including muscle pain, insomnia, trembling, and gastro-intestinal problems.

Panic Disorder

One of the most common anxiety disorders is panic disorder. It is often present with depression and affects 2.5 million Americans every year, most often young adults. Panic disorder is periodic attacks of anxiety or terror, often brought on unexpectedly and without reason. In general, the attacks last 15 to 30 minutes. It is common for the attacks to occur in a public place such as a restaurant or mall. The frequency of panic attacks vary -- for some people it may happen every week, while for others it may occur every few months. Because there seems to be no obvious explanation for why a panic attack starts, the fear of having another one can affect the way a person lives. For example, if the attack occurs in a mall, then the person may stop going to the mall in an attempt to avoid another one. This can lead to avoiding other large public places. It is not uncommon for a panic disorder to develop into phobias of these places or situations.

For somebody to be diagnosed with panic attack, they must have at least four of the following symptoms and have had four or more attacks within a four-week period; accompanied by concern about having other attacks, worry over the implications of the attack (like fear of death from a heart attack), and altered behavior (like avoiding a particular place) because of the attack.

• Fast heart beat
• Extreme sweating
• Shortness of breath
• Shakiness
• A choking sensation
• Dizziness
• Nausea
• Numbness
• Hot flashes/chills
• Chest pain
• Fear of dying
• Feeling of losing control

Social Phobia

Also known as social anxiety, this disorder causes attacks of excessive self-consciousness in social situations. These situations can range from public speaking, to signing one's name in front of people, to eating in a restaurant. Whatever the case may be, for those people who suffer from social phobia, these situations create an intense and constant feeling of being watched, judged, and negatively evaluated. This intense fear of public humiliation often forces those affected by social phobia to go out of their way to avoid these types of situations, which can have a negative affect on their personal and professional lives.

Social phobia is a common disorder, affecting over 5 million people in a given year. It often begins in childhood and rarely develops after age 25. People with social phobia are often aware that their fears are irrational but are unable to lessen or erase these fears.

The symptoms of social phobia are much the same as they are for other anxiety disorders, and include trembling, or shaking, intense sweating, nausea, difficulty talking, dry mouth, and a racing heart. Like other anxiety illnesses these symptoms range from being mild and tolerable to so severe that they become socially debilitating.

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