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Selective Noradrenaline Reuptake Inhibitor (SNRI) — Non-stimulant ADHD Treatment Pregnancy: Avoid — limited data; animal studies show developmental toxicity at high doses. Discuss risk-benefit with specialist if ADHD medication essential in pregnancy.

Atomoxetine

Brand names: Strattera

Adult dose

Dose: ADHD: 40mg OD initially for 7 days; increase to 80mg OD (or divided BD); maximum 100mg OD after 2–4 weeks if needed. Take with or without food.
Route: Oral
Frequency: Once daily (morning) or divided BD (morning and evening)
Max: 100mg OD
Non-stimulant — not a controlled drug (advantage over methylphenidate for patients with substance misuse history or where controlled drug prescribing is problematic). Onset is slower than stimulants (2–4 weeks for full effect). May be taken at night if sedation is beneficial. Licensed for ADHD in children ≥6 years, adolescents, and adults. NICE second-line after methylphenidate.

Paediatric dose

Dose: 0.5 mg/kg
Route: Oral
Frequency: Once daily or twice daily
Max: 1.2mg/kg/day or 100mg (whichever lower)
BNFc / NICE NG87: Children ≥6 years (≤70kg): 500 micrograms/kg OD for 7 days; increase to 1.2mg/kg OD or divided BD (max 1.2mg/kg/day or 100mg). Children >70kg: adult dosing. Specialist ADHD assessment required.

Dose adjustments

Renal

No dose adjustment required.

Hepatic

Moderate hepatic impairment: reduce dose by 50%. Severe hepatic impairment: reduce dose by 75%.

Paediatric weight-based calculator

BNFc / NICE NG87: Children ≥6 years (≤70kg): 500 micrograms/kg OD for 7 days; increase to 1.2mg/kg OD or divided BD (max 1.2mg/kg/day or 100mg). Children >70kg: adult dosing. Specialist ADHD assessment required.

Clinical pearls

  • Not a controlled drug — preferred over methylphenidate in patients with personal or family history of substance abuse, or in settings where stimulant diversion is a concern
  • Black-box warning: suicidal ideation in children and adolescents — monitor weekly in first 4 weeks, then every 2 weeks for 4 months; provide patient/carer with emergency contact information
  • CYP2D6 poor metabolisers (7–10% of population): naturally have higher atomoxetine levels — same dose may cause more side effects; reduce dose if side effects prominent
  • Slower onset than stimulants: full therapeutic effect takes 4–6 weeks — do not switch prematurely; ensure patient is counselled about delayed onset

Contraindications

  • Severe cardiovascular disease or uncontrolled hypertension
  • Narrow-angle glaucoma
  • Phaeochromocytoma
  • MAOIs (within 14 days)
  • Hypersensitivity to atomoxetine

Side effects

  • Decreased appetite, nausea (common at initiation)
  • Dry mouth
  • Insomnia or somnolence
  • Tachycardia and BP elevation
  • Urinary hesitancy (noradrenergic — alpha-1 effect)
  • Suicidal ideation (rare but black-box warning — monitor in first weeks)
  • Hepatotoxicity (rare — monitor LFTs if jaundice or abdominal pain)
  • Sexual dysfunction (adults)
  • Growth effects (similar to stimulants)

Interactions

  • MAOIs — contraindicated (severe cardiovascular reactions)
  • Strong CYP2D6 inhibitors (paroxetine, fluoxetine) — increase atomoxetine levels 6–8 fold; reduce atomoxetine dose significantly when combined
  • Salbutamol (albuterol) — additive cardiovascular effects; monitor BP and HR

Monitoring

  • Blood pressure and heart rate (baseline; every 3–6 months)
  • Height and weight (6 monthly in children)
  • Liver function (if jaundice or abdominal pain)
  • Suicidality (first 4 weeks — weekly review)
  • ADHD symptom rating

Reference: BNFc; BNF 90; NICE NG87 (ADHD); Strattera SPC. Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

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