Atomoxetine, formerly sold under the brand name Strattera,[12] is a selective norepinephrine reuptake inhibitor (sNRI) medication used to treat attention deficit hyperactivity disorder (ADHD)[13] and, to a lesser extent, cognitive disengagement syndrome (CDS).

[17][18] It enhances the executive functions of self-motivation, sustained attention, inhibition, working memory, reaction time,[19] and emotional self-regulation.

[22][23][24][25] Common side effects of atomoxetine include abdominal pain, decreased appetite, nausea, feeling tired, and dizziness.

[8] Meta-analyses and systematic reviews have found that atomoxetine has comparable efficacy and equal tolerability to methylphenidate in children and adolescents.

Atomoxetine alleviates ADHD symptoms through norepinephrine reuptake inhibition and by indirectly increasing dopamine in the prefrontal cortex,[34] sharing 70-80% of the brain regions with stimulants in their produced effects.

[35] Unlike α2-adrenergic receptor agonists such as guanfacine and clonidine, atomoxetine's use can be abruptly stopped without significant withdrawal symptoms being observed.

[37][39] The maximum recommended total daily dose in children and adolescents is 70 mg and adults is 100 mg.[5] Atomoxetine may be used to treat cognitive disengagement syndrome (CDS),[15] as multiple randomised controlled clinical trials (RCTs) have found that it is an effective treatment.

[40][41][42][43] Atomoxetine is sometimes used in the treatment of cognitive impairment and frontal lobe symptoms due to conditions like traumatic brain injury (TBI).

[13][26] A 2020 meta-analysis found that atomoxetine was associated with anorexia, weight loss, and hypertension, rating it as a "potentially least preferred agent based on safety" for treating ADHD.

[8][52] Unlike stimulant medications, atomoxetine does not have abuse liability or the potential to cause withdrawal effects on abrupt discontinuation.

[55] Other notable drug interactions include: Atomoxetine prevents norepinephrine release induced by amphetamines and has been found to reduce the stimulant, euphoriant, and sympathomimetic effects of dextroamphetamine in humans.

[68] However, both mouse and rat microdialysis studies have failed to find an increase in extracellular serotonin in the prefrontal cortex following acute or chronic atomoxetine treatment.

[69] Atomoxetine has been found to act as an NMDA receptor antagonist in rat cortical neurons at therapeutic concentrations.

[74][75] Atomoxetine also reversibly inhibits GIRK currents in Xenopus oocytes in a concentration-dependent, voltage-independent, and time-independent manner.

[10] Japanese men homozygous for CYP2D6*10 have similarly been found to experience two-fold higher AUCs compared to extensive metabolizers.

Atomoxetine may be quantitated in plasma, serum, or whole blood to distinguish extensive versus poor metabolizers in those receiving the drug therapeutically, to confirm the diagnosis in potential poisoning victims, or to assist in the forensic investigation in a case of fatal overdosage.

[84] On 12 August 2010, Lilly lost a lawsuit that challenged its patent on Strattera, increasing the likelihood of an earlier entry of a generic into the US market.

[86] In a 29 July 2011 conference call, however, Sun Pharmaceutical's Chairman stated "Lilly won that litigation on appeal so I think [generic Strattera]'s deferred.

[89] In India, atomoxetine is sold under brand names including Axetra, Axepta, Attera, Tomoxetin, and Attentin.

In Australia, Canada, Italy, Portugal, Romania, Spain, Switzerland, and the US, atomoxetine is sold under the brand name Strattera.

[92] As with other norepinephrine reuptake inhibitors it appears to reduce anxiety and depression symptoms, although research has focused mainly on specific patient groups such as those with concurrent ADHD[93] or methamphetamine dependence.