Ramelteon for Sleep Initiation Insomnia in Individuals With Panic Disorder Who Are Also on Escitalopram for Anxiety

Inclusion Criteria: * 1\) Clinical diagnosis of panic disorder * 2\) Difficulty initiating sleep (subjective sleep latency (SL) of \>30 minutes) for at least 3 times per week in the preceding month. Exclusion Criteria: * 1)Patients meeting DSM-IV criteria (as determined by MINI) for a current anxiety disorder (other than panic disorder), or current major depressive disorder that is considered by the investigator to be primary (i.e., causing a higher degree of distress or impairment than panic disorder)., Patients with past history of DSM-IV anxiety disorders or depressive disorder will not be excluded. * 2\) Patients with current psychotic disorder, current bipolar disorder, or substance use disorder (except nicotine dependence) or Subjects with significant suicide risk. * 3\) Candidates with known sensitivity to any selective serotonin reuptake inhibitors (SSRI) will be excluded. * 4\) CNS diseases: Candidates with seizure disorder (other than febrile seizure in early childhood), a history of other neurological disorder, and head trauma will be excluded. * 5\) Cardiovascular and respiratory diseases: Candidates with hypertension (systolic \>130; diastolic \> 85), arrhythmias, coronary artery disease, cardiac pacemakers, COPD, asthma, and other pulmonary diseases will be excluded. * 6\) Primary sleep disorders: Candidates with breathing related sleep disorder, restless leg syndrome, circadian rhythm sleep disorders, narcolepsy, and other major primary sleep disorders will be excluded. * 7\) Systemic diseases: Candidates with other medical problems, such as endocrinopathies, renal or hepatic failure, autoimmune diseases involving the CNS, obesity (BMI \> 30 kg/m2), or a history of pheochromocytoma will not be eligible. * 8\) Consumption of greater than 720 mgs. of caffeine daily. * 9\) History of shift work (11 PM to 7 AM) in the past 6 months. * 10\) Reproductive status: Women candidates who are pregnant (based on urine test) are not eligible. Women of child bearing age will be on birth control methods during the study period. * 11\) Individuals with personality, behavior, or medical disorders likely to interfere with study participation.