Alter procedure in mysql
According to MySQL Docs, you can alter a procedure using ALTER PROCEDURE, unless you need to change the procedure's parameters or it body.


  This statement can be used to change the characteristics of a stored procedure. More than one change may be specified in an ALTER PROCEDURE statement. However, you cannot change the parameters or body of a stored procedure using this statement; to make such changes, you must drop and re-create the procedure using DROP PROCEDURE and CREATE PROCEDURE.