After taking a dose of Methylprednisolone tablet from a Medrol Dosepak it should be out of your system after approximately 13 to 20 hours.

Methylprednisolone tablets have an elimination half-life of approximately 2.5 hours to 3.5 hours. This is the time it takes for the drug levels in your plasma to reduce by half.
It takes approximately 5.5 times the elimination half-life for a medicine to be cleared from your body which is (5.5 x 2.5 hours) 13.75 hours to (5.5 x 3.5 hours) 19.25 hours.

Therefore the time for a methylprednisolone tablet to be removed from your body is approximately 13 to 20 hours.

Note: Depo-Medrol injection contains methylprednisolone acetate which has a longer half life and is a long acting injection.

Other factors to consider:
1. How much and how often you have taken the drug.
2. Your metabolic rate – a slower metabolism will increase the time a drug remains in your system.
3. Your age and health – older age and poor health will generally increase the time the drug stays in your system.
4. Body mass – generally the bigger you are the longer a drug will remain in your system.