I wonder if anyone can advise me:

I want to teach abroad, preferably in Japan.

I have osteoarthitis in my left ankle, and despite it, i walk with a (very) slight limp, for 2 hours a day min, along with managing stairs no problem. I do however, take codeine based medication to keep my symptoms under control.

what my concern is this is:

will I be automtatically disqualified/ineligible to teach in Japan as a direct result of either my medication or my arthitis?
2) Would i be automatically be disqualified/ineligible to teach in the Japanese schools, on the basis of either my medication or my arthitis?