Atomoxetine

Atomoxetine is a selective noradrenaline reuptake inhibitor. By keeping more noradrenaline available in the parts of the brain that govern attention and impulse control, it helps to steady concentration, curb restlessness and reduce acting on impulse. The UK SmPC licenses it for ADHD in children from six years of age, in adolescents and in adults, as part of a wider programme that usually includes psychological, educational and social support. Treatment should be started by a clinician experienced in ADHD, and in adults the symptoms must have been present since childhood for the diagnosis to stand.

Methylphenidate and lisdexamfetamine work quickly and are Controlled Drugs. Atomoxetine has a different profile: it carries little potential for misuse and gives cover throughout the day and into the evening rather than in peaks. The trade-off is patience, because it can take two to four weeks before any change is noticed and up to around three months for the full response. It is often chosen when stimulants have not suited someone, when tics or anxiety are a concern, or when there is a history of substance misuse in the household.

The 10 mg and 18 mg strengths here come in packs of 30, 60, 90, 120, 180 and 360; 25 mg is offered in packs of 30 to 180. UK products are hard capsules made in 10, 18, 25, 40, 60, 80 and 100 mg. Dosing depends on body weight. For children and teenagers up to 70 kg, the SmPC suggests about 0.5 mg per kg each day for at least a week, then a usual maintenance level of about 1.2 mg per kg daily. Those over 70 kg and adults start on 40 mg daily for at least a week, with 80 mg as the usual maintenance dose and 100 mg the recommended maximum. The daily amount may be taken in the morning or split between morning and late afternoon. The small strengths offered here are mainly suited to starting doses or to lighter children; your prescriber decides the regimen.

Atomoxetine is a prescription-only medicine (POM). It was first marketed in Britain as Strattera by Eli Lilly, and generic capsules from several manufacturers are now also licensed. It is not listed as a Controlled Drug, so the extra prescription rules that apply to stimulants do not cover it.

This medicine should not be taken with a monoamine oxidase inhibitor (MAOI) or within two weeks of stopping one. It is also contraindicated in narrow-angle glaucoma, phaeochromocytoma and in severe heart or blood vessel disease, including serious cardiovascular or cerebrovascular disorders where a rise in pulse or blood pressure would be risky. Fluoxetine, paroxetine and other strong CYP2D6 inhibitors can raise blood levels considerably, so a slower dose increase may be needed. Salbutamol given by injection or in high doses, and medicines that prolong the QT interval or lower the seizure threshold, also call for caution.

Reduced appetite, stomach ache, nausea, headache and sleepiness are common early on and often settle. Heart rate and blood pressure tend to rise slightly, so they are checked before starting and at intervals afterwards, as are height and weight in children. The patient leaflet warns about suicidal thoughts and mood changes, especially in young people; any new low mood, agitation or self-harming ideas should be reported to the doctor promptly. Liver injury is rare but serious: dark urine, yellowing skin or pain under the right ribs mean stopping the medicine and seeking advice.

Swallow capsules whole with water, with or without food; they should not be opened, as the contents irritate the eyes. Atomoxetine can be stopped without tapering, yet any change should be agreed with the clinician who manages the ADHD. Whether this treatment is appropriate, and at what dose, is a decision for your doctor or prescriber.