What is the half-life of Clonidine (clonidine)?

From the FDA Drug Label

The pharmacokinetics of clonidine is dose-proportional in the range of 100 to 600 mcg. ... Following intravenous administration, clonidine displays biphasic disposition with a distribution half-life of about 20 minutes and an elimination half-life ranging from 12 to 16 hours.

• The half-life of Clonidine is approximately 12 to 16 hours for patients with normal renal function.
• In patients with severe impairment of renal function, the half-life can increase up to 41 hours 1

From the Research

The half-life of clonidine is approximately 12-16 hours in adults with normal renal function, as supported by the most recent and highest quality study available 2. This means it takes about 12-16 hours for half of the drug to be eliminated from the body. However, this half-life can be significantly longer (up to 41 hours) in patients with impaired kidney function, as clonidine is primarily eliminated through the kidneys. The extended half-life explains why clonidine is typically dosed twice daily for conditions like hypertension or attention deficit hyperactivity disorder. Some key points to consider when prescribing clonidine include:

• The drug's effectiveness in managing conditions that require sustained drug levels throughout the day, such as hypertension, ADHD, anxiety, and certain pain syndromes.
• The importance of tapering the dose gradually when discontinuing clonidine to avoid rebound hypertension or withdrawal symptoms.
• The potential for interindividual variation in renal clearance, which can affect the plasma clonidine concentration produced by a particular transdermal dose 3.
• The linear pharmacokinetics of clonidine, which allows for predictable dose-response relationships 4.
• The similarity in pharmacokinetic and pharmacodynamic profiles between oral and sublingual routes of administration 5. Overall, the half-life of clonidine is an important consideration in its clinical use, and healthcare providers should be aware of the potential for variability in this parameter based on individual patient factors.