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Xeljanz (tofacitinib) accounted for 10% new prescriptions in the United States in 2017. In that year alone, there were over 100,000 prescriptions. As more people take this medication, it pays to know more about it, including how long Xeljanz will stay in your system.

The FDA states the following information regarding Xeljanz half-life in the body:

Mean effective half-life: Xeljanz – 3 hours; Xeljanz XR – 6 hours

Time to steady-state: Xeljanz – 24 to 48 hours for twice-daily administration; Xeljanz XR – 48 hours for once-daily administration

Mean accumulation ratio: There is negligible accumulation for both Xeljanz/Xeljanz XR after daily administration

Terminal phase half-life: 3.2 hours for Xeljanz and 5.9 hours for Xeljanz XR

Xeljanz has an oral bioavailability of 74%, which refers to the amount of the drug that becomes absorbed into the body. When taken with high-fat meals, there were no changes to the area under plasma concentration-time curve (AUC) for both the immediate release and extended release formulas. The AUC refers to how much of the drug enters the bloodstream during a given period of time.

Tofacitinib is metabolized into the system at approximately 70% while 30% is excreted from the body. A part of the Xeljanz XR may be passed in the stools. Never crush, chew, or split the extended release tablets.


What is the half-life of Xeljanz?

Half-life refers to how long it takes for the body to clear half of a substance. This half-life timespan will vary when taking immediate release pills and extended release pills. The half-life for Xeljanz is 3 hours after taking 2 daily doses and 6 hours after taking one dose of Xeljanz XR.

How long does Xeljanz stay in your system?

It will depend on whether you are taking the immediate release formula of Xeljanz or the extended-release tablets of Xeljanz XR, as well as your body’s absorption rate, metabolism and excretion rate.

With High-fat Meals

During random clinical studies, the maximum plasma concentration (Cmax) was reduced by 32% for Xeljanz when the drug was taken with a high-fat meal. This factor means that if you take Xeljanz with meals that contain high levels of fat, the amount of the drug that is concentrated in the plasma within your blood will be reduced. So the length of time that the tofacitinib was detected in plasma was lower.

For Xeljanz XR, the Cmax was increased by 27% when taken with a high-fat meal. The time for maximum plasma concentration (Tmax) for Xeljanz XR was extended for 1 hour. So, the extended-release tablets stayed in the blood/plasma for an extended length of time by one hour before reaching half-life.

In Regards to Drug Testing

These factors are important when you are undergoing drugs tests and therapeutic drug testing. Medical professionals will perform these tests on patients to determine the amount of the drug that will stay in the system, so they can adjust the dosage amounts to safe levels. These adjustments help to minimize and prevent prolonged side effects.

How long does it take for Xeljanz to get out of your system?

There is negligible accumulation of Xeljanz/Xeljanz XR in the body. In addition, it is metabolized at a rate of 70% and excreted from the body at a rate of 30%. It has a half-life of 3 hours.

How long does Tofacitinib take to work?

It will depend on the patient who is taking the medication. Some patients have seen results in a few weeks. Other patients have seen results in a few months.

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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