Class: α2-Adrenergic Agonist
Dosage Forms. Tablet: 0.1 mg, 0.2 mg, 0.3 mg; Tablet, Extended Release: 0.1 mg, 0.2 mg; Transdermal Patch: 0.1 mg/24 h, 0.2 mg/24 h, 0.3 mg/24 h
Common FDA Label Indication, Dosing, and Titration.
1. Attention deficit hyperactivity disorder: Children >6 y, 0.1 mg extended-release tablet po qhs, may titrate in increments of 0.1 mg/d at weekly intervals to desired effect; give doses >0.1 mg/d in 2 divided doses; max dose 0.4 mg/d
2. Essential hypertension: 0.1 mg/d transdermal patch applied every 7 d, may titrate by 0.1 mg/d transdermal patch increments every 1-2 wk; max 0.6 mg/d every 7 d
3. Hypertension: 0.1 mg po bid, may titrate by 0.1 mg/d at weekly intervals, to 0.2-0.6 mg in 2 divided doses, max 2.4 mg/d
Off-Label Uses.
1. Hot sweats: 0.1 mg/d transdermal patch every 7 d or 0.2 mg po daily
2. Nicotine dependence: 0.1-0.2 mg/24 h transdermal patch daily or 0.1-0.45 mg po daily
3. Spasticity: 0.05-0.4 mg po daily in divided doses
MOA. Clonidine stimulates postsynaptic α2-adrenergic receptors in the CNS by activating inhibitory neurons to decrease sympathetic outflow. Clonidine is not a complete agonist, so some of its effects might result from antagonist actions at presynaptic α-receptors. These actions reduce peripheral vascular resistance, renal vascular resistance, heart rate, and BP.
Drug Characteristics: Clonidine
Medication Safety Issues: Clonidine
Drug Interactions: Clonidine
Adverse Reactions: Clonidine
Efficacy Monitoring Parameters. Decreased BP or improvement of mental and behavioral symptoms of ADHD.
Toxicity Monitoring Parameters. Rebound hypertension, increased heart rate, palpitations, syncope.
Key Patient Counseling Points. Avoid alcohol, CNS depressants. Caution with driving and other tasks requiring alertness. Swallow extended-release tablet whole, may be taken with or without food. Apply patch to hairless area of intact skin on upper outer arm or chest; rotate patch location. If patch loosens during the 7-d wearing, secure adhesive cover. Report signs/symptoms of hypotension, exacerbation of angina peripheral edema, fatigue, hypotension, or hepatic dysfunction with initial dosing and dose changes. Avoid abrupt discontinuation to avoid rebound hypertension.
Clinical Pearls. Safety and efficacy of the immediate-release tablet for the treatment of hypertension not established in children. Extended-release tablets and immediate-release tablet formulation are not interchangeable.