Overview
11 DESCRIPTION Atomoxetine, USP is a selective norepinephrine reuptake inhibitor. Atomoxetine hydrochoride is the R (-) isomer as determined by x-ray diffraction. The chemical designation is (-)- N -Methyl-3-phenyl-3-( o -tolyloxy)-propylamine hydrochloride. The molecular formula is C 17 H 21 NO•HCl, which corresponds to a molecular weight of 291.81.
Mechanism of Action
12 CLINICAL PHARMACOLOGY 12.1 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 in ex vivo uptake and neurotransmitter depletion studies. 12.2 Pharmacodynamics An exposure-response analysis encompassing doses of atomoxetine (0.5, 1.2 or 1.8 mg/kg/day) or placebo demonstrated atomoxetine exposure correlates with efficacy as measured by the Attention-Deficit/Hyperactivity Disorder Rating Scale-IV-Parent Version: Investigator administered and scored.
Indications
- 1 INDICATIONS AND USAGE Atomoxetine capsule is a selective norepinephrine reuptake inhibitor indicated for the treatment of Attention-Deficit/Hyperactivity Disorder (ADHD). ( 1.1 ) 1.1 Attention-Deficit/Hyperactivity Disorder (ADHD) Atomoxetine capsule is indicated for the treatment of Attention-Deficit/Hyperactivity Disorder (ADHD). The efficacy of atomoxetine capsules was established in seven clinical trials in outpatients with ADHD: four 6 to 9-week trials in pediatric patients (ages 6 to 18), two 10-week trial in adults, and one maintenance trial in pediatrics (ages 6 to 15) [see Clinical...
Common Doses
- 0.5 mg
- 1.2 mg
- 1.4 mg
- 40 mg
Dosage
2 DOSAGE AND ADMINISTRATION Initial, Target and Maximum Daily Dose ( 2.1 ) (Acute and Maintenance/Extended Treatment) Body Weight Initial Daily Dose Target Total Daily Dose Maximum Total Daily Dose Children and adolescents up to 70 kg 0.5 mg/kg 1.2 mg/kg 1.4 mg/kg Children and adolescents over 70 kg and adults 40 mg 80 mg 100 mg Dosing adjustment — Hepatic Impairment, Strong CYP2D6 Inhibitor, and in patients known to be CYP2D6 poor metabolizers (PMs). ( 2.4 , 12.3 ) 2.
Black Box Warning
WARNING: SUICIDAL IDEATION IN CHILDREN AND ADOLESCENTS Atomoxetine increased the risk of suicidal ideation in short-term studies in children or adolescents with Attention-Deficit/Hyperactivity Disorder (ADHD). Anyone considering the use of atomoxetine in a child or adolescent must balance this risk with the clinical need. Co-morbidities occurring with ADHD may be associated with an increase in the risk of suicidal ideation and/or behavior.
Contraindications
- 4 CONTRAINDICATIONS • Hypersensitivity to atomoxetine or other constituents of product. ( 4.1 ) • Atomoxetine capsules use within 2 weeks after discontinuing MAOI or other drugs that affect brain monoamine concentrations. ( 4.2 , 7.1 ) • Narrow Angle Glaucoma. ( 4.3 ) • Pheochromocytoma or history of pheochromocytoma.( 4.4 ) • Severe Cardiovascular Disorders that might deteriorate with clinically important increases in HR and BP. ( 4.5 ) 4.
Side Effects
- 6 ADVERSE REACTIONS Most common adverse reactions (≥5% and at least twice the incidence of placebo patients) • Child and Adolescent Clinical Trials – Nausea, vomiting, fatigue, decreased appetite, abdominal pain, and somnolence. ( 6.1 ) • Adult Clinical Trials – Constipation, dry mouth, nausea, decreased appetite, dizziness, erectile dysfunction, and urinary hesitation. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Annora Pharma Private Limited at 1-866-495-1995 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.
Interactions
- 7 DRUG INTERACTIONS • Monoamine Oxidase Inhibitors. ( 4.2 , 7.1 ) • CYP2D6 Inhibitors - Concomitant use may increase atomoxetine steady-state plasma concentrations in EMs. ( 7.2 ) • Antihypertensive Drugs and Pressor Agents – Possible effects on blood pressure. ( 7.3 ) • Albuterol (or other beta 2 agonists) - Action of albuterol on cardiovascular system can be potentiated. ( 7.4 ) 7.1 Monoamine Oxidase Inhibitors With other drugs that affect brain monoamine concentrations, there have been reports of serious, sometimes fatal reactions (including hyperthermia, rigidity, myoclonus, autonomic...