What attention-deficit hyperactivity disorder (ADHD) treatment alternatives are available for a child who has an adverse reaction to stimulants? Atomoxetine (Strattera) has been ineffective.
—Janine Fiorello, PNP, Farmingdale, N.Y.
Be sure that ADHD is the only diagnosis you are treating. If there are comorbid conditions, there may be additional therapeutic possibilities.
As you know, stimulants are first-line treatment for ADHD. Many formulations are now available. If one doesn’t seem to work, another might. However, if all stimulants cause adverse effects and atomoxetine has been ineffective, then second- or third-line therapies may be tried.
Bupropion, an aminoketone antidepressant, has been shown to decrease ADHD symptoms but is not as efficacious as stimulants. Side effects include decreased seizure threshold, drowsiness, irritability, insomnia, fatigue, headache, dry mouth, sweating, constipation, nausea, and dermatologic reactions. This medication also requires electroencephalographic monitoring.
Tricyclic antidepressants (TCAs) presumably inhibit norepinephrine and dopamine reuptake and are effective in decreasing ADHD symptoms. These drugs, which have more impact on behavioral symptoms than on cognitive symptoms, are not as effective as stimulants. TCAs could be a good choice in children with comorbid depression or tic disorder. Advantages are a long half-life (12 hours), lack of abuse potential, and positive effects on mood, anxiety, and sleep. Side effects include drowsiness, dizziness, dry mouth, sweating, blurred vision, constipation, weight gain, and changes in heart rate and BP. Most important, however, are the cardiovascular risks of lengthening the QT interval and potential heart block. Careful monitoring of heart rate and ECG is required. Unlike bupropion, overdose causes severe toxicity.
The alpha-adrenergic agonists clonidine (e.g., Catapres) and guanfacine (Tenex) have also been used to treat ADHD symptoms. These agents have been shown to decrease sleep disturbance, aggression, and tics (especially when used as an adjunct therapy to stimulants). Unfortunately, such side effects as sedation, drowsiness, depression, orthostatic hypotension, cardiac arrhythmias (slowed sinus rate and conduction delays are rare but serious), and rebound hypertension if stopped abruptly have limited their use.
Other drugs still being investigated are venlafaxine (Effexor), donepezil (Aricept), tacrine (Cognex), and the nicotinic analog ABT-418. For more, see Eur Child Adolesc Psychiatry. 2004;13 Suppl 1:I102-116.
—Julee B. Waldrop, MS, PNP (125-8)