Hi. Thanks for your question. I am a board certified neurologist in the U.S.
Haloperidol can indeed produce stiffness reactions which can sometimes be permanent. Sometimes, but not always, these problems of Parkinson's like symptoms can be alleviated by taking medications which increase dopamine levels for Parkinson's disease, such as Carbidopa-Levodopa, Pramipexole, or similar agents. This would need to be discussed with a neurologist to see if this could be an option for you. Other medication options which can be considered includes the anticholinergic class of medications, such as Benztropine. Again, no guarantee that they will help, but they would be reasonable treatment options to try to lessen the leg stiffness which was caused by chronic use of Haldol.