Atomoxetine

Strattera treats ADHD in adults and pediatric patients age 6 or older as part of a program that may include psychological, educational and social measures. Assess the diagnosis, functional needs and other psychiatric/medical causes before treatment.

Safety/effectiveness below age 6 are not established. Atomoxetine is not a controlled substance and is not approved to treat depression. This profile covers current U.S. capsules; extemporaneous liquids, other-country formulations and stimulant conversion algorithms are outside its scope.

Give once each morning or evenly divided between morning and late afternoon/early evening, with or without food. Swallow capsules whole; do not open. For a missed dose, take as soon as possible without exceeding the prescribed total daily amount in any 24 hours. No taper is required when stopping under the treatment plan. Periodically reassess long-term benefit; higher-than-target dosing has limited added efficacy and must remain within the stated maximum.

Current label initial and target doses: Child–Pugh A, usual doses; B, 50% of usual; C, 25% of usual. These percentages refer to initial/target doses, not a separately specified hepatic maximum or an algorithm for acute drug-induced injury. Jaundice or laboratory evidence of injury requires discontinuation without restart.

Consider CYP2D6 testing. With a strong CYP2D6 inhibitor or known poor metabolism, current label starting, target and maximum amounts remain the same as its dose table, but wait 4 weeks before increasing if symptoms remain inadequate and the initial dose is tolerated. Other metabolizer types use the standard minimum 3-day interval.

The current PK study found ESRD exposure differences not clinically significant after weight correction and supplies no separate renal-reduction algorithm. Monitor BP and tolerability. Keep at least 14 days between stopping an MAOI antidepressant and starting atomoxetine, and at least 14 days after stopping atomoxetine before starting an MAOI.

Known atomoxetine/excipient hypersensitivity; MAOI use or within 14 days after stopping; narrow-angle glaucoma; pheochromocytoma or its history; and severe cardiac/vascular disease expected to deteriorate with clinically important BP or pulse increases. Linezolid and IV methylene blue are included MAOI examples in the interaction section.

The current box warns of suicidal thoughts and behaviors in pediatric patients age 6 or older. Short-term pooled studies found suicidal ideation in 0.4% (5/1,357) on atomoxetine versus none (0/851) on placebo; one treated patient attempted suicide and no suicides occurred in those studies. The adult analysis did not show increased risk, but that does not remove clinical observation or urgent response to suicidality.

Common pediatric effects include nausea, vomiting, fatigue, appetite reduction, abdominal pain and sleepiness. Common adult effects include constipation, dry mouth, nausea, reduced appetite, dizziness, erectile dysfunction and urinary hesitation. Postmarketing reports include QT prolongation, syncope, Raynaud phenomenon and seizures; frequency/causality cannot be reliably established from voluntary reports. CYP2D6 poor metabolizers have greater exposure and may have more adverse effects.

Do not combine with MAOIs, including linezolid or IV methylene blue. Serious or fatal hyperthermia, rigidity, autonomic instability and mental-status reactions may occur. Maintain the 14-day separation in both directions for MAOI antidepressant switching; emergency MAOI treatment requires a clinician-directed plan.

Fluoxetine and paroxetine markedly increase atomoxetine exposure in patients who are not poor metabolizers. Follow the current four-week titration interval and assess BP, pulse and adverse effects when inhibitors are added or removed. Known CYP2D6 poor metabolizers already have high exposure; do not invent one combined inhibitor/genotype dose multiplier.

Use cautiously with antihypertensives, pressors or other drugs that raise BP; increase BP monitoring and adjust clinically. Systemically administered albuterol can have enhanced pulse/BP effects with atomoxetine; the label advises closer BP/pulse monitoring with albuterol or other beta2 agonists. Do not assume every inhaled regimen has the same magnitude as the systemic interaction study.

Human pregnancy studies are insufficient to establish drug-associated risks; animal developmental effects are reported. Consider maternal treatment needs and available alternatives; the label identifies an ADHD-medication pregnancy registry. Human milk, infant-effect and milk-production data are absent in the selected label; weigh breastfeeding benefits, maternal need and potential infant effects.

ADHD efficacy/safety are established from age 6, not below 6. Closely follow growth, appetite, cardiovascular effects and daily behavioral observations. Geriatric efficacy, safety and PK have not been evaluated adequately; there is no validated age-only dose algorithm.

Moderate and severe hepatic impairment increased exposure approximately twofold and fourfold, supporting the initial/target reductions. Poor CYP2D6 metabolism produces about tenfold AUC and fivefold peak exposure versus other types and needs slower titration. The studied ESRD difference disappeared after mg/kg correction; the current label does not provide a renal-dose table. Consider all comorbidities rather than treat PK alone as proof of safety.

The precise therapeutic mechanism is unknown; atomoxetine is thought to act through selective inhibition of the presynaptic norepinephrine transporter. It is not a controlled stimulant, and the label’s abuse study did not find stimulant/euphoriant properties.

Current label estimates oral bioavailability at 63% in other CYP2D6 metabolizer types and 94% in poor metabolizers; median peak times are 1 and 2.5 hours, respectively. Protein binding is about 98%; half-life approximately 5.2 versus 21.6 hours. CYP2D6 forms active 4-hydroxyatomoxetine, rapidly glucuronidated; other enzymes contribute slower metabolism. More than 80% of the dose is excreted in urine as the glucuronide and less than 3% as unchanged drug. Food lowers/delays peaks without changing AUC.

Before treatment assess bipolar risk and cardiac history/exam, baseline BP/pulse and pediatric height/weight. Recheck BP/pulse after dose increases and periodically; track growth, appetite, tolerability and ADHD benefit. Families should observe behavior daily, especially early and during dose changes. Order liver tests at the first signs/symptoms of dysfunction rather than invent a fixed screening interval; obtain ECG/other cardiac testing when clinically indicated.

Read the Medication Guide and promptly report suicidal or severe behavioral changes, liver symptoms, exertional chest pain/fainting, inability to urinate or priapism. Swallow capsules whole. If contents contact an eye, flush immediately with water and obtain advice; wash hands and contaminated surfaces. Use caution driving until effects on alertness are known. Discuss medicines, pregnancy and sexual adverse effects with the clinician.

Contact Poison Control or a medical toxicologist promptly for overdose. Symptoms can include GI upset, somnolence, agitation, tachycardia, increased BP, tremor, seizures or QT prolongation. Mixed-drug overdoses have caused deaths; reported absence of single-agent fatalities is not a safety guarantee. High protein binding makes dialysis unlikely to help.

Product

Strattera 40 mg capsule

Route

Oral; prescription, noncontrolled

Appearance

Opaque blue / opaque blue; LILLY 3229

Example package

30 capsules · NDC 0002-3229-30

Selected Strattera capsules contain 10, 18, 25, 40, 60, 80 or 100 mg atomoxetine base as hydrochloride. Other generic capsule appearances/NDCs differ. This review does not authorize opening capsules, compounding a suspension or transferring other-country liquid doses.

Store at 25°C (77°F), with permitted excursions to 15–30°C (59–86°F). Keep in the labeled container and out of children’s reach. Capsule powder is an ocular irritant; handle accidental exposure as described in Counseling. No universal opened-container discard interval is supplied by the selected label.