OverviewDosageSide EffectsInteractionsHalf-Life

Prednisone is currently the 22nd most commonly prescribed drug in the United States. In 2020 alone, there are so far over 25,028,445 prescriptions. Considering how widely used this medication is, it pays to know a little more about it, including how long prednisone stays in your system.

How long does prednisone stay in your system?

Mean effective half-life: 3 to 4 hours (prednisone); 2 to 3.5 hours (prednisolone)

Terminal phase half-life: 2.7 +/- 0.3 hours (prednisolone)

Prednisone is likely detectable in your system for the following time frames:

Urine: 35 hours – 132 hours

According to one study, prednisone could be detectable in urine anywhere between under 35 hours to over 132 hours after last use; prednisolone was detectable for a briefer period

Saliva: One study found that the mean max concentration of prednisolone in saliva was “381 +/- 114 ng/mL” after 1 hour, which drastically reduced to roughly 100 ng/mL after 6 hours; prednisone reached a mean max concentration of 122 +/- 40 ng/mL after nearly 2 hours, and these values remained largely unchanged for the next 4 hours

Plasma: One study found that the mean max concentration (total serum) of prednisolone reached “992 +/- 246 ng/mL after 1.5 +/- 60.6 hours” while prednisone reached 50 +/- 6 ng/mL (total serum) and 28 +/- 4 ng/mL (free serum); while prednisone total serum values dipped after peaking, free serum values remained largely stable for several hours

(Numbers above are merely estimates, and may vary based on several factors, such as age and other medical conditions.)

Prednisone has an oral bioavailability of roughly 70%, with prednisolone bioavailability being about 80% after an oral dose of prednisone. Liver enzymes metabolize, or convert, prednisone to prednisolone, and its metabolites are excreted primarily via the renal (kidney) system.

What is the half-life of prednisone?

In this context, half-life refers to how long it takes for the body to reduce its concentration of prednisone in half.

– In typical adults without abnormal liver functioning, the half-life of prednisone is about 3 to 4 hours.

Note that it takes more than 2 half-lives for the body to completely eliminate this drug.

What is the peak time for prednisone?

Prednisone and prednisolone will typically reach peak plasma concentrations in adults after about 1 to 3 hours.

How long does it take for adrenal glands to recover after prednisone?

Considering how prednisone and prednisolone work, it should come as no surprise that they can influence the adrenal glands. Specifically, long-term use of glucocorticoids—the class to which prednisone belongs—may negatively affect the adrenal system. Located on top of the kidneys, the small adrenal glands produce important hormones like cortisol.

Several factors influence the recovery time of the adrenal system, including age, dosage, and length of treatment.

What are the side effects of short-term prednisone use?

For more information, please visit our page on prednisone side effects.

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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