Alpha-2 adrenergic agonist
Stimulates central alpha-2 receptors, reducing sympathetic outflow, which lowers blood pressure and modulates noradrenergic activity involved in attention, arousal, and autonomic regulation.
Hypertension, attention-deficit/hyperactivity disorder (ADHD) in children aged 6 years and older
Opioid withdrawal, Tourette syndrome, anxiety disorders, sleep disturbances, post-traumatic stress disorder (PTSD)-related hyperarousal and sleep disturbances, agitation and aggression in neurodevelopmental disabilities (especially with hyperactivity or impulsivity)
Oral tablets, transdermal patch
Start at 0.1 mg p.o. nightly, titrate slowly based on clinical response, typical dose range 0.1–0.3 mg/day
0.1–0.3 mg/day
Half-life approximately 12–16 hours, metabolized hepatically, excreted renally
Drowsiness, dry mouth, constipation, hypotension, fatigue
Rebound hypertension with abrupt discontinuation—taper gradually
Monitor blood pressure and heart rate regularly, especially during dose changes or discontinuation
None
Use caution in elderly patients due to increased risk of hypotension and orthostatic falls. Clonidine may improve impulsivity and irritability in intellectual disabilities and neurodevelopmental disorders. In traumatic brain injury (TBI), it is used off-label for posttraumatic headache prophylaxis and trauma-related nightmares, particularly when comorbid with PTSD.