Panic Disorder 213
the case of only limited-symptom unexpected panic attacks, an other specified anxiety dis-
order or unspecified anxiety disord er diagnosis should be considered.
Anxiety disorder due to another medical condition. Panic disorder is not diagnosed if
the panic attacks are judged to be a direct physiological consequence of another medical
condition. Examples of medica l conditions that can cause panic attacks include hyperthy-
roidism, hyperparathyroidism, pheochromocytoma, vestibular  dysfunctions, seizure dis-
orders, and cardiopulmonary conditions (e.g., arrhythmias, supraventricular tachycardia,
asthma, chronic obstructive pulmonary diseas e [COPD]). Appropriate laboratory tests
(e.g., serum calcium levels for hyperparathy roidism; Holter monitor for arrhythmias) or
physical examinations (e.g., for cardiac conditions) may be helpful in determining the eti-
ological role of another medical condition. 
Substance/medication-induced anxiety disorder. Panic disorder is not diagnosed if
the panic attacks are judged to be a direct physiological consequence of a substance. In-
toxication with central nervou s system stimulants (e.g., co caine, amphetamines, caffeine)
or cannabis and withdraw al from central nervous system depressants (e.g., alcohol, bar-
biturates) can precipitate a panic attack. Howe ver, if panic attacks continue to occur out-
side of the context of substance use (e.g., long after the effects of intoxication or withdrawal
have ended), a diagnosis of panic disorder should be cons idered. In addition, because
panic disorder may precede substance use in some individuals and may be associated
with increased substance use, especially for pu rposes of self-medicat ion, a detailed history