Clonidine Dosing for Hypertension and ADHD
Hypertension Dosing
For hypertension, start clonidine at 0.1 mg twice daily (morning and bedtime), then increase by 0.1 mg per day at weekly intervals as needed, with typical maintenance doses ranging from 0.2-0.6 mg daily in divided doses and a maximum effective dose of 2.4 mg daily. 1
Standard Dosing Protocol
- Initial dose: 0.1 mg twice daily (morning and bedtime) 1
- Titration: Increase by 0.1 mg per day at weekly intervals until desired blood pressure response is achieved 1
- Maintenance range: 0.2-0.6 mg per day in divided doses (most commonly employed therapeutic range) 1
- Maximum effective dose: 2.4 mg per day, though doses this high are rarely needed 1
- Dosing strategy: Taking the larger portion of the daily dose at bedtime minimizes transient side effects like dry mouth and drowsiness 1
Special Populations
- Elderly patients: Benefit from a lower initial dose 1
- Renal impairment: Lower initial dose recommended with careful monitoring; no supplemental dosing needed after hemodialysis 1
Hypertensive Crisis (Rapid Oral Titration)
For severe hypertension requiring urgent control, a rapid oral loading protocol can be used:
- Initial loading dose: 0.1-0.2 mg orally 2, 3
- Subsequent doses: 0.05-0.1 mg hourly until goal blood pressure is achieved or maximum total dose reached 2
- Maximum total dose: 0.7-0.8 mg 2, 3
- Success rate: Achieves significant blood pressure reduction in 93% of patients 2
- Response time: Average 1.8 hours with mean dose of 0.32 mg 4
This rapid titration approach is effective and safe for most hypertensive urgencies, though caution is warranted in patients with symptomatic arteriosclerotic disease 4, 2.
ADHD Dosing
For ADHD, start clonidine at 0.05-0.1 mg at bedtime, then increase by 0.1 mg in divided doses (BID-TID) to a maximum of 0.4 mg per day. 5, 6
Standard ADHD Protocol
- Initial dose: 0.05-0.1 mg at bedtime 5, 6
- Titration: Increase by 0.1 mg in divided doses (BID-TID) 5
- Maximum dose: 0.4 mg per day 5, 6
- Timing: Evening dosing is often preferred due to sedative effects 6
- Onset of effect: Full therapeutic benefit may take 2-4 weeks to develop 6
Important Context for ADHD Use
The American College of Obstetricians and Gynecologists notes that clonidine can be considered as an adjunct agent for ADHD treatment following risk-benefit discussion, acknowledging limited information on both safety and efficacy in adults 5, 6. Limited data are available on the efficacy, safety, and tolerability of clonidine for ADHD treatment in adults 5.
Critical Safety Precautions
Discontinuation Protocol
Clonidine must always be tapered to avoid rebound hypertension—abrupt discontinuation can induce hypertensive crisis. 7, 6
This is the most critical safety consideration with clonidine use, as the American College of Cardiology and Circulation guidelines emphasize the risk of severe rebound hypertension with sudden cessation 7.
Common Side Effects
- Somnolence and fatigue 6
- Dry mouth 6
- Irritability, insomnia, and nightmares 6
- Significant CNS adverse effects (reason it's reserved as last-line antihypertensive in adults, especially elderly) 7
Serious Adverse Effects Requiring Monitoring
- Hypotension 6
- Bradycardia 6
- Syncope 6
- Regular monitoring of blood pressure and heart rate is essential 6
Special Populations: Pregnancy and Breastfeeding
Pregnancy
- Clonidine can be used during pregnancy for hypertension or hyperemesis gravidarum with no increased risk for major or minor malformations 5, 6
- A recent large, well-controlled study demonstrated no increased risks for clonidine use during pregnancy on long-term outcomes 5
- Clonidine crosses the placental barrier 7, 6
Breastfeeding
- Caution is advised during breastfeeding 5
- Clonidine is found in human milk and detectable in infant serum following breastfeeding exposure 5
- Milk-to-plasma ratio: 2, with relative infant dose up to 7.1% 5, 6
- Breastfed infants should be monitored for drowsiness and hypotonia 5, 7, 6
- One case report documented an infant developing drowsiness, hypotonia, suspected seizures, and apnea with maternal dose of 0.15 mg daily; all symptoms resolved within 24 hours of breastfeeding cessation 5
Formulations Available
Clinical Positioning
The American College of Cardiology recommends clonidine as a last-line antihypertensive agent due to significant CNS adverse effects, particularly in older adults 7, 6. However, it remains useful for specific indications including ADHD as adjunct therapy and hypertensive urgencies requiring rapid control 7, 2.