Ohio Rev. Code Ann. § 3121.12
(A) On receipt of a notice that a lump sum payment of one hundred fifty dollars or more is to be paid to the obligor, the court, with respect to a court support order, or the child support enforcement agency, with respect to an administrative child support order, shall do either of the following:
(C) A court that issued an order prior to January 1, 1998, requiring an employer to withhold an amount from an obligor's personal earnings for the payment of support shall issue a supplemental order that does not change the original order or the related support order requiring the employer to do all of the following: