Many different classes of drugs1 have been utilized in the treatment attention-deficit/hyperactivity disorder (ADHD), also called attention deficit disorder. Here we will describe the side effects of a selected list of ADHD therapeutics by their generic names.
Amphetamine-derived stimulants work by increasing the synaptic concentrations of dopamine and norepinephrine.2 These drugs were historically used to treat obesity, and common side effects include loss of appetite, increased wakefulness, sleep disturbances and low risk of suicidal thoughts and psychotic symptoms. Drugs used to treat ADHD include:
Methylphenidate This drug may also cause the worsening of tics an increased risk of seizures.
Amphetamine This drug may also cause growth delay in children and an increase in heart rate and blood pressure. Sudden withdraw of amphetamine can cause symptoms such as depression and sever fatigue, especially after regular usage over an extended period of time.
Secondary Tricyclic antidepressants
While the mechanism of action of this class of drugs is unknown, these molecule have been observed to increase the synaptic concentrations of serotonin and norepinephrine.3 Common side effects of these drugs include daytime drowsiness, dizziness, blurred vision, dry mouth, urinary disturbances, constipation and sexual problems. The drugs used for ADHD include:
Tertiary Tricyclic antidepressants
These molecules are very similar to the secondary tricyclic antidepressants in their activities and side effects, however the side effects tend to be more pronounced and also include potential cardiotoxicity and increased frequency of seizures.3 The drugs used for ADHD include:
Monoamine Oxidase (MOA) Inhibitors increase synaptic concentrations of dopamine, norepinephrine and serotonin by slowing their breakdown.3 These inhibitors can be used as an antidepressant, and their side effects include irregular heartbeat, increased heart rate, sexual disturbances, increased difficulty falling and staying asleep, daytime insomnia, tremors in the arms and hands, headache, confusion, anxiety, agitation, dry mouth, constipation, gastro-intestinal disturbances, edema, weight gain, weakness, dizziness and dizziness upon standing that can lead to fainting. Drugs used to treat ADHD include:
Phenelzine This is an irreversible inhibitor of two forms of MAO that can be prescribed for depression. Its effects can last for up to two weeks after cessation of its use.
Selegiline This s an irreversible inhibitor of one form of MAO that can be prescribed for Parkinson’s disease. Its side effects include orthostatic hypotension and hallucinations.
α2-adernergic agonists can be used to treat high blood pressure.3 Common side effects for this class of drugs include abnormally slow heart action, drowsiness, tiredness, dizziness, weakness, headache and dry mouth. Less frequent side effects include ringing in the ears, increased urinary frequency, urinary retention, sexual dysfunction, nasal congestion, blurred vision and dry eyes. Drugs used to treat ADHD include:
Clonidine Most side effects of clonidine are mild and tend to diminish with continued usage. Combination therapy of clonidine and methylphenidate can negatively affect cardiac condition and increase patient risk for arrhythmia. Withdraw symptoms of this drug include nervousness, agitation, restlessness, anxiety, insomnia, tremor, headache, sweating, increased salvation, increased blood pressure and irregular or increased heart rate.
Guanfacine This drug has side effects similar to clonidine, but has milder withdraw symptoms that rarely include hypertension.
Atomoxetine Atomoxetine prolongs the action of norepinephrine in the brain. Its side effects include modest increases in diastolic blood-pressure and heart rate, drowsiness, dry mouth, skin rash, dizziness, nausea, weight loss, and anorexia.3
Modafinil Modafinil is a wake-promoting used to treat narcolepsy, but has many off-label uses including ADHD treatment.4 The most common side effects include insomnia, abdominal pain, anorexia, cough, fever and stuffy nose.1
- Lancet: Attention-deficit Hyperactivity Disorder
- Cortese, S.et al. Practitioner review: current best practice in the management of adverse events during treatment with ADHD medications in children and adolescents. J Child Psychol Psychiatry 2013, 54, 227-46.
- Foye's Principles of Medicinal Chemistry. 7 ed.; Lippincott Williams & Wilkins: 2012.
- Ballon, J. S.; Feifel, D. A systematic review of modafinil: Potential clinical uses and mechanisms of action. J Clin Psychiatry 2006, 67, 554-66.