A Study of Sertraline and Early Alprazolam XR Administration Versus Sertraline Only in Panic Disorder Patients

Inclusion Criteria: * Subjects will include men and women over the age of eighteen; * the ability to give written informed consent; * current principal or co-principal psychiatric diagnosis of panic disorder with or without agoraphobia based on DSM-IV criteria (American Psychiatric Association, 1994); * willing to use an effective means of contraception; * free of psychoactive medications for at least 2 weeks prior to study enrollment; * not actively be suicidal. Exclusion Criteria: * actively suicidal; * medical conditions for which either sertraline or alprazolam XR would be contraindicated; * recent six month history of substance or alcohol abuse; * history or presence of psychotic or bipolar disorder; * women who are pregnant or breastfeeding; * history or presence of a seizure disorder or a known history of more than one childhood febrile seizure; * presence of a personality disorder severe enough to compromise the investigator's ability to evaluate the efficacy and safety of the study medication; * concomitant therapy with other psychotropic medication(s); * clinically significant abnormality during physical examination, vital signs, EKG, urine drug screen, or laboratory tests at the screen visit.