The investigators hypothesize that trazodone does not worse nocturnal oxygen saturation in insomnic ischemic stroke patients with obstructive sleep apnea (OSA) and depression and has beneficial effect in selected stroke patients with low arousal threshold phenotype OSA.

Inclusion Criteria:

• Insomnic ischemic stroke patients with OSA and depression.

Exclusion Criteria:

• unclear consciousness, unstable vital sign or neurologic sign, unstable medical conditions such as delirium, active infection, evidence of overt congestive cardiac failure, liver dysfunction with ascites, thyroid disease, end-stage-renal-disease receiving dialysis.
• overnight mean oxygen saturation (SaO2) nadir is ≤ 70% at baseline
• take monoamine oxidase inhibitors (MAOI), any medication that may affect breathing, sleep, or muscle activity
• any known allergy to trazodone
• sleep disorder other than OSA (e.g., periodic leg movement syndrome, restless legs syndrome, central sleep apnea/Cheyne-Stokes respiration).