Yes, you should reduce your medical expense deduction by the amount your ex-spouse paid you in reimbursements. Your spouse is entitled to deduct medical expenses that he pays as well:
Child of divorced or separated parents.
For purposes of the medical and dental expenses deduction, a child of divorced or separated parents can be treated as a dependent of both parents. Each parent can include the medical expenses he or she pays for the child, even if the other parent claims the child's dependency exemption, if:
The child is in the custody of one or both parents for more than half the year,
The child receives over half of his or her support during the year from his or her parents, and
The child's parents:
Are divorced or legally separated under a decree of divorce or separate maintenance,
Are separated under a written separation agreement, or
Live apart at all times during the last 6 months of the year.
This doesn't apply if the child's exemption is being claimed under a multiple support agreement (discussed later).
