Atomoxetine Hydro Chloride

atomoxetine hydrochloride (at oh mox' ah teen) Strattera Pregnancy Category C Drug class

Selective norepinephrine reuptake inhibitor Therapeutic actions

Selectively blocks the reuptake of norepinephrine at the neuronal synapse. The mechanism by which this action has a therapeutic effect in attention deficit hyperactivity disorder (ADHD) is not understood. Indication

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Treatment of ADHD as part of a total treatment program

Contraindications and cautions

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Contraindicated with hypersensitivity to atomoxetine or constituents of Strattera; use of MAOIs within the past 14 days; narrow-angle glaucoma Use cautiously with hypertension, tachycardia, CV or cerebrovascular disease, pregnancy, lactation

Pharmacokinetics Route Oral

Onset Rapid

Peak 1–2 hr

Metabolism: Hepatic; T1/2: 5 hr Distribution: May cross placenta; may enter breast milk Excretion: Urine and feces Available forms

Capsules—10, 18, 25, 40, 60 mg Dosages ADULTS AND CHILDREN > 70 KG

40 mg/day PO, increase after a minimum of 3 days to a target total daily dose of 80 mg PO given as a single dose in the morning or two evenly divided doses, in the morning and late afternoon or early evening; after 2–4 wk, total dosage may be increase to a maximum of 100 mg/day if needed. PEDIATRIC PATIENTS < 70 KG

Initially, 0.5 mg/kg/day PO, increase after a minimum of 3 days to a target total daily dose of approximately 1.2 mg/kg/day PO as a single daily dose in the morning; may be given in two evenly divided doses in the morning and late afternoon or early evening. Do not exceed 1.4 mg/kg or 100 mg/day, whichever is less. PATIENTS WITH HEPATIC IMPAIRMENT

For moderate hepatic impairment, reduce dose to 50% of the normal dose; for severe hepatic impairment, reduce dose to 25% of the normal dose. Adverse effects

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CNS: Aggression, irritability, crying, somnolence, dizziness, headache, mood swings, insomnia CV: Palpitations Dermatologic: Dermatitis, increased sweating GI: Dry mouth, nausea, dyspepsia, flatulence, decreased appetite, constipation, upper abdominal pain, vomiting GU: Urinary hesitation, urinary retention, dysmenorrhea, erectile problems Respiratory: Cough, rhinorrhea, sinusitis Other: Fever, rigors, sinusitis, weight loss, myalgia

Interactions

Drug-drug • Possible increased serum levels if combined with potent CYP2D6 inhibitors— paroxetine, fluoxetine, quinidine; monitor and adjust dosage of atomoxetine to 0.5 mg/kg/day with a target dose of 1.2 mg/kg/day for children < 70 kg or 40 mg/day with a target dose of 80 mg/day for children > 70 kg or adults • Risk of neuroleptic malignant syndrome if combined with MAOIs; do not combine with an MAOI and do not give atomoxetine within 14 days of using an MAOI Nursing considerations Assessment

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History: Hypersensitivity to atomoxetine or constituents of Strattera; use of MAOIs within the past 14 days; narrow-angle glaucoma, hypertension, tachycardia, CV or cerebrovascular disease, pregnancy, lactation Physical: Height, weight, T; skin color, lesions; orientation, affect; P, BP, auscultation; R, adventitious sounds; bowel sounds, normal output

Interventions

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Ensure proper diagnosis before administering to children for behavioral syndromes: drug should not be used until other causes and concomitants of abnormal behavior (learning disability, EEG abnormalities, neurological deficits) are ruled out. Ensure that drug is being used as part of an overall treatment program including education and psychosocial interventions. Arrange to interrupt drug dosage periodically in children being treated for behavioral disorders to determine if symptoms recur at an intensity that warrants continued drug therapy. Monitor growth of children on long-term atomoxetine therapy. Administer drug before 6 PM to prevent insomnia if that is a problem. Monitor blood pressure early in treatment, particularly with adult patients.

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Arrange for consult with school nurse of school-age patients receiving this drug. For women of childbearing age who are using this drug, suggest using contraceptives.

Teaching points

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Take this drug exactly as prescribed. It can be taken once a day in the morning, if adverse effects are a problem, the drug can be taken in two evenly divided doses in the morning and in the late afternoon or early evening. Take drug before 6 PM to avoid night-time sleep disturbance. Avoid the use of alcohol and over-the-counter drugs, including nose drops, cold remedies, and herbal therapies while taking this drug; some of these products cause dangerous effects. If you feel that you need one of these preparations, consult your health care provider. The effects of this drug on the unborn baby are not known, women of childbearing age are advised to use contraceptives. These side effects may occur: Dizziness, insomnia, moodiness (these effects may become less pronounced after a few days; avoid driving a car or engaging in activities that require alertness if these occur; notify your health care provider if these are pronounced or bothersome); headache (analgesics may be available to help), loss of appetite, dry mouth (eat small, frequent meals and suck on sugarless lozenges). Report palpitations, dizziness, weight loss, severe dry mouth and difficulty swallowing, pregnancy.

Adverse effects in Italic are most common; those in Bold are life-threatening.