Anxiety is a feeling of worry, uneasiness, fear, apprehension, or misgiving about something that has happened, might have happened, or might yet happen in the future. Often, it can produce tension symptoms in the body as well as in the mind.

Some forms of anxiety, including panic attacks, may be consequences of medical disorders such as hyperthyroidism or seizure disorders. Other forms can be induced by overstimulation of the central nervous system with chemicals such as cocaine, amphetamines, nicotine, or caffeine, or by the withdrawal of central nervous system depressants, such as alcohol or barbiturates.

Anxiety may also be psychological in origin or have psychological components, as is frequently the case with medically-based anxiety. This kind of anxiety often includes fears and phobias, as well as apprehensions about performing personally, socially, or sexually.

While all forms of anxiety that are directly related to physiological medical conditions should be evaluated for treatment by a psychiatrist or other medical doctor, most forms including medically-based anxieties can benefit from the attention and insight offered through traditional psychotherapy. Often, a combination of medical and psychological intervention can be most helpful.