The Collaborative International Dictionary of English v.0.48:

Forspent \For*spent"\, a. [AS. forspendan to consume; pref. for-
   + spendan to spend.]
   Wasted in strength; tired; exhausted. [Archaic]
   [1913 Webster]

         A gentleman almost forspent with speed.  --Shak.
   [1913 Webster]