From the Guidelines
Clonidine helps ADHD by reducing hyperactivity, impulsivity, and inattention symptoms through its action on alpha-2 adrenergic receptors in the brain, and it is typically prescribed at 0.1-0.4 mg per day, often divided into multiple doses, with treatment usually starting at a low dose (0.1 mg) and gradually increasing as needed 1.
Key Points
- Clonidine works by increasing norepinephrine activity in the prefrontal cortex, which improves executive functioning and impulse control 1.
- It's available in immediate-release tablets taken 2-4 times daily or extended-release (Kapvay) taken once daily, usually at bedtime 1.
- Common side effects include drowsiness, fatigue, dry mouth, and occasionally lowered blood pressure 1.
- While not a first-line treatment like stimulants, clonidine is particularly useful for patients with ADHD who also have tics, sleep problems, or aggression, or for those who cannot tolerate stimulant medications 1.
- The medication typically takes 2-4 weeks to show full therapeutic effects, and patients should not stop taking it abruptly as this can cause rebound hypertension 1.
Important Considerations
- Clonidine can be used as an adjunctive therapy with stimulant medications, and it has been shown to be effective in reducing ADHD symptoms in children and adolescents 1.
- The dosage of clonidine should be carefully titrated to minimize side effects, and patients should be monitored regularly for changes in blood pressure, heart rate, and other potential side effects 1.
- Clonidine may be a good option for patients who have not responded to stimulant medications or who have significant side effects from stimulants 1.
From the Research
Mechanism of Action
- Clonidine, an α(2)-adrenergic agonist, is used to treat attention-deficit hyperactivity disorder (ADHD) in children and adolescents 2.
- The exact mechanism of how clonidine helps ADHD is not fully understood, but it is believed to improve symptoms by acting on the brain's neurotransmitters 3.
Efficacy
- Clonidine has been shown to improve symptoms of ADHD in children and adolescents, particularly in those with hyperarousal, hyperactivity, and aggressivity symptoms 2, 3.
- Studies have demonstrated that clonidine can reduce symptoms of ADHD, including hyperactivity and impulsivity, with significant improvements seen after 2 weeks of treatment 2, 4.
- Clonidine has been found to be effective as monotherapy and as adjunctive therapy with stimulant regimens in clinical trials 2, 5.
Comparison with Other Treatments
- Clonidine has been compared to methylphenidate, a common treatment for ADHD, and has been found to have different effects on target symptoms 3, 6.
- Clonidine has been shown to be more effective in improving hyperactivity and impulsivity symptoms, while methylphenidate is more effective in improving attention-deficit symptoms 3, 6.
- Clonidine has also been compared to carbamazepine, another second-line treatment for ADHD, and has been found to be more effective in improving hyperactivity and impulsivity symptoms 4.