atomoxetine for adhd

Atomoxetine: (why is this the most efficacious for adhd vs. other SNRIs?)

• selective norepinephrine reuptake inhibitor
• only FDA approved SNRI for adhd
• used as second-line therapy after trial of atl east 2 stimulant agents 
• slower onset of action than stimulants (does not work immediately, takes ~2 weeks to see effect)
• no abuse potential
• less potential to cause growth effects in comparison to stimulant agents
• good for comorbid anxiety disorders, tics
• adverse effects: nausea, anorexia, insomnia, sedation, liver toxicity, priapism
• metabolized through cyp 2D6
• need to be dose reduced in hepatic impairment
• no renal dose adjustments
• potential for drug drug interactions with 2D6 inhibitors or inducers
• pathogenesis of ADHD: involved with hypoactivity of dopamine and norepinephrine in frontal-subcortical circuits in brain
• atomoxetine works strictly on norepinephrine
• other SNRIs (duloxetine and venlafaxine) work on serotonin and norepinephrine
• mostly work on serotonin, starts to work on norepinephrine only with HIGH doses
• more efficacious to use an SNRI that has more effect on norepinephrine vs serotonin as that is the catecholamine affected in ADHD
• there is weak evidence to use duloxetine in ADHD although not FDA approved for this use
• 1 RCT compared duloxetine to placebo showed some benefit, but further studies needed
• no RCTs comparing duloxetine to atomoxetine