OverviewDosageSide EffectsInteractionsHalf-Life

Clonidine was the 73rd most commonly prescribed drug in the United States in 2017. In 2018 alone, there were over 11 million prescriptions. Considering how popular this drug is right now, it pays to know a little bit more about this medication, including how long clonidine stays in your system.

Basic Information

Mean effective half-life: 12 to 16 hours (less for oral absorption and longer for patches)

Time to steady-state: Plasma peak time is one to three hours.

Mean accumulation ratio: NA

Terminal phase half-life: 12 to 16 hours

Clonidine has an oral bioavailability of 70 to 80 percent. About half of the dose once absorbed is metabolized by the liver and then 40 to 60 percent is recovered and excreted in the urine.  


What is the half-life of clonidine?

The half-life for clonidine is 12 to 16 hours. (less for oral absorption and longer for patches)

How long does clonidine stay in your system?

Clonidine is detectable in your system for the following time frames:

  • Your blood for less than 24 hours
  • Your saliva for NA.
  • Your hair for NA.

Clonidine is not a drug that would show up in all types of testing. It leaves the body quickly enough that it is unlikely to show up in the blood longer than a few hours. It is possible it might be detected in urine for up to three days, though. 

What is the duration of action of clonidine?

Clonidine peaks in just 60 to 90 minutes for an oral dose. It lasts in the body for 32 hours or less. 

Does drowsiness from clonidine go away?

It may go away over time but it’s hard to say for sure. People experiencing extreme drowsiness should talk to their doctor.

Disclaimer: this article does not constitute or replace medical advice. If you have an emergency or a serious medical question, please contact a medical professional or call 911 immediately. To see our full medical disclaimer, visit our Terms of Use page.

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