Panic disorder is relatively common; similar rates have been found in
many countries in international studies. Approximately one third of the
individuals with panic disorder also have agoraphobia, although in
clinical settings, the majority present with some agoraphobia. Panic disorder
with agoraphobia is diagnosed about twice as frequently in females as in
The most common age of onset is middle teens and early adulthood;
however, panic disorder may onset at any time. A common pattern of onset is
the occurrence of occasional unexpected panic attacks that then increase
infrequency and are associated with mounting fears of having subsequent
attacks. Over time there is often a pattern of spreading fearful avoidance.
Little is known about the long-term course of this disorder. The
limited findings to date suggest that in most cases it is a chronic disorder
that waxes and wanes in severity. However, some people may have a limited
period of dysfunction that never recurs, while others may experience a severe
chronic form of the disorder. Those with agoraphobia tend to have a more
severe and complicated course. Treatment early in the development of this
disorder may shorten the duration and may prevent complications, including
agoraphobia and depression.

Comorbidity: Associated Disorders
Certain conditions have been found to be associated with panic
disorder, particularly in those individuals with long-standing panic attacks
and agoraphobia. These conditions include abuse of alcohol and drugs,
depression, and other anxiety and personality disorders. Other medical
disorders that occur more commonly in patients with panic disorder may
include atypical chest pain, irritable bowel syndrome, asthma, and migraine.

Comorbid Conditions
There are three kinds of medical conditions that may affect treatment
planning and may need to be treated concurrently. These are (1) conditions
that may affect the safety or efficacy of psychopharmacological treatments
(such as some specific cardiovascular, pulmonary, gastrointestinal, or
endocrine disorders; pregnancy; or lactation); (2) conditions with a
prominent component of anxiety (such as thyroid disease, polycythemia, lupus,
and pulmonary insufficiency); and (3) conditions requiring treatment with
medications such as vasoconstrictors, bronchodilators, or steroids, which may
cause or exacerbate anxiety. The necessity for a complete psychological
assessment in addition to the medical workup cannot be overemphasized. 
Up to 70 percent of patients with panic disorder may have a comorbid
psychological or psychiatric condition that will need to be included in the
treatment planning and perhaps addressed therapeutically concomitantly or at
a later point. A high percentage are depressed or demoralized secondary to
suffering panic attacks but should be treated for panic first. Other
conditions such as major depression, posttraumatic stress disorder, bipolar
mood disorder, dissociative disorders, other anxiety disorders such as
obsessive compulsive disorder or social phobia, eating disorders, or complex
personality disorders may require concurrent treatment. Finally, individuals
need to be assessed explicitly regarding substance abuse, including alcohol,
marijuana, opiates, hallucinogens, cocaine, over-the-counter drugs such as
nasal sprays and diet pills, caffeinism, or benzodiazepine abuse. 
Patients in current withdrawal or active abuse must be treated for
substance abuse before or concurrent with specific panic disorder treatment.

Patient Fit and Compliance Issues
The clinician, in consultation with the patient, should select one of
the treatments with demonstrated efficacy or a combination as the initial
treatment. Selection should be based on patient preference in the context of
a comprehensive assessment of urgency, history, and comorbidity. It may be
the case that the selected treatment will require referral, consultation, or
supervision. The individual with panic disorder needs to be an active, fully
informed participant in the treatment planning process. Education and
demystification are frequently needed. This means advising the patient not
only of the short-term benefits and risks but also of long-term benefits and
risks where known and addressing the issue of long-term relapse prevention. 
The patient's initial degree of relief and motivation following
education may give direction to the next step. Attitudes and concerns
regarding various treatment options must be explored and negotiated. The
patient's request in presenting for treatment must be kept in mind. Answering
questions such as "why me?" or "why now?" or "what is this about?" may
establish a better foundation for treatment. Patients should be given
education about the disorder and encouragement to re-enter phobic situations
gradually when medication alone is chosen as the initial treatment. 
Current research suggests that an absence of any noticeable improvement
after about 6 to 8 weeks of any treatment should suggest a reassessment,
consultation, or change of modality. Particularly for those patients for whom
there has been a chronic course or a history of multiple episodes of acute
symptomatology, recovery, and relapse, longer term strategies need to be
considered following the acute phase of treatment. 
Unfortunately, at this time, little is known regarding the relative
long-term efficacy of maintenance doses of medication, other psychotherapies,
changes in lifestyle aimed at stress reduction, or participation in ongoing
self-help groups. These current practices have been shown to be of value in
other disorders and may in the future be shown to beso in panic disorder as
well. As with many other treatable disorders, access to effective care is at
times limited by regulatory decisions, lack of financial resources,
inadequate third party coverage, and stigma.

Source: National Institute of Health