Hi i've been on prednisone 10mg for the last 2 months how long will it take to leave my system cheers?

Taper the dose: Long-term prednisone suppresses the normal hormonal production by your adrenal gland. The dose should be tapered (over 2-4 weeks) rather than being abruptly stopped.

Short time: The half life of Prednisone itself is short, around 1 hour. Meaning that within few hours the serum/plasma levels are basically zero. Nevertheless, the effects of Prednisone ( anti-inflammatory and immunoregularoty ) and the side effects ( if they have occurred ) persist for days to weeks.