Atomoksetin

Atomoksetin, also known as atomoxetine, is a medication approved for the treatment of attention-deficit/hyperactivity disorder (ADHD) in children, adolescents, and adults. It is a selective norepinephrine reuptake inhibitor (NRI) and is not classified as a stimulant. By blocking the norepinephrine transporter, atomoksetin increases norepinephrine availability in neural circuits involved in attention and executive function, with a comparatively smaller effect on dopamine in the prefrontal cortex.

Indications and usage: Atomoksetin is used as monotherapy for ADHD and may be chosen when stimulant medications are ineffective, contraindicated, or not preferred. Onset of symptom improvement can take several weeks, and response varies among individuals.

Pharmacology: Atomoksetin is taken orally and has relatively low bioavailability due to first-pass metabolism. It is extensively metabolized by hepatic enzyme CYP2D6 to an active metabolite, 4-hydroxyatomoksetin. The drug shows variable half-life depending on CYP2D6 metabolic status. Dosing is individualized; pediatric starting doses are commonly around 0.5 mg/kg per day with gradual titration, and adults may begin around 40 mg per day, increasing as tolerated up to about 80–100 mg per day in many guidelines.

Side effects and safety: Common adverse effects include nausea, decreased appetite, dry mouth, sleep disturbance, dizziness, and elevated blood pressure or heart rate. Rare but serious risks include hepatotoxicity and, in young people, mood changes or suicidality. Caution is advised when used with monoamine oxidase inhibitors or strong CYP2D6 inhibitors due to interaction potential.

Regulatory status: Atomoksetin is available by prescription in many countries. Brand names include Strattera, with generic formulations also widely available.