High-frequency Repetitive Transcranial Magnetic Stimulation Targeting Left Dorsolateral Prefrontal Cortex for Depression Ameliorates Insomnia yet Triggers Excessive Daytime Sleepiness: A Catch-22 Situation

Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive brain stimulation technique that is effective and safe for the treatment of depression. We observed improvement in insomnia along with symptoms of depression following high-frequency rTMS over the left dorsolateral prefrontal cortex in a patient with treatment-resistant depression, which progressed to excessive daytime sleepiness during the treatment sessions. Causality assessment suggested a probable association of rTMS with excessive sleepiness. The implications of the effect of rTMS on sleep are discussed.