Product Details

ATOMOXETINE

Atomoxetine is the first non-stimulant drug approved for the treatment of attention-deficit hyperactivity disorder (ADHD). It is sold in the form of the hydrochloride salt of atomoxetine.

Indication

For the treatment of Attention-Deficit/Hyperactivity Disorder (ADHD) alone or in combination with behavioral treatment, as an adjunct to psychological, educational, social, and other remedial measures.

Associated Conditions

• Attention Deficit Disorder With Hyperactivity (ADHD)

Pharmacodynamics

Atomoxetine is the first non-stimulant drug approved for the treatment of attention-deficit hyperactivity disorder (ADHD). Atomoxetine is classified as a norepinephrine reuptake inhibitor, and is approved for use in children, adolescents, and adults. However, its efficacy has not been studied in children under six years old. Its advantage over stimulants for the treatment of ADHD is that it has less abuse potential than stimulants, is not scheduled as a controlled substance and has proven in clinical trials to offer 24 hour coverage of symptoms associated with ADHD in adults and children.

Mechanism of action

The precise mechanism by which atomoxetine produces its therapeutic effects in Attention-Deficit/Hyperactivity Disorder (ADHD) is unknown, but is thought to be related to selective inhibition of the pre-synaptic norepinephrine transporter, as determined through in-vitro studies. Atomoxetine appears to have minimal affinity for other noradrenergic receptors or for other neurotransmitter transporters or receptors.

Absorption

Atomoxetine is rapidly absorbed after oral administration, with absolute bioavailability of about 63% in EMs and 94% in PMs. Drugs that elevate gastric pH (magnesium hydroxide/aluminum hydroxide, omeprazole) have no effect on atomoxetine bioavailability. Absorption is minimally affected by food.

Volume of distribution

• 0.85 L/kg

Protein binding

At therapeutic concentrations, 98% of atomoxetine in plasma is bound to protein, primarily albumin.

Metabolism

Atomoxetine is primarily metabolized by the CYP2D6 pathway to 4-hydroxyatomoxetine. 4-Hydroxyatomoxetine is equipotent to atomoxetine as an inhibitor of the norepinephrine transporter but circulates in plasma at much lower concentrations (1% of atomoxetine concentration in EMs and 0.1% of atomoxetine concentration in PMs).

• Atomoxetine
   
  4-hydroxyatomoxetine

Route of elimination

Not Available

Half life

5 hours

Clearance

• 0.35 L/hr/kg [after oral administration in adult extensive metabolizers]
• 0.03 L/hr/kg [administration of atomoxetine to poor metabolizers]

Toxicity

The most commonly reported symptoms accompanying acute and chronic overdoses are somnolence, agitation, hyperactivity, abnormal behavior, and gastrointestinal symptoms.

Affected organisms

• Humans and other mammals

Food Interactions

• In the presence of food, the absorption rate is reduced, without the quantity absorbed being affected.
• Take without regard to meals.

SOURCE:DRUGBANK