Table 2.

Potential rTMS treatment protocols for MDD with and without comorbid psychiatric disorders

Diagnosis	Potential rTMS protocols	Rationale
MDD (including anxious depression)	Left sided HF-rTMS; Right sided LF-rTMS; Bilateral rTMS	Prefrontal asymmetry theory in depression
MDD ＋ Anxiety disorders	Right sided LF-rTMS; Bilateral rTMS	Hyperactive right DLPFC in anxiety
MDD ＋ PTSD	Insufficient evidence to make recommendations; Left sided 5-Hz rTMS, right sided HF-rTMS, and right sided iTBS warrant further researches	Abnormal frontal theta (4−7 Hz) activity in PTSD Associations between hypoactive HPA axis and right hypofrontality
MDD ＋ Substance use disorders	Insufficient evidence to make recommendations; Left sided HF-rTMS warrants further researches	Hypoactive left DLPFC in patients with substance dependence

rTMS, repetitive transcranial magnetic stimulation; MDD, major depressive disorder; PTSD, posttraumatic stress disorder; HF, high frequency; LF, low frequency; iTBS, intermittent theta-burst stimulation; DLPFC, dorsolateral prefrontal cortex; HPA, hypothalamic-pituitary-adrenal.