If you and your spouse file separate returns and one of you itemizes deductions, the other spouse will not qualify for the standard deduction and should also itemize deductions.
You may be able to claim itemized deductions on a separate
return for certain expenses that you paid separately or jointly with your spouse.
Deductible expenses that are paid out of separate funds, such as medical expenses,
are deductible by the spouse who pays them. If these expenses are paid from
community funds, the deduction may depend on whether or not you live in a community
property state. In a community property state, the deduction is divided equally
between you and your spouse.