Federal income taxes withheld from a retirement plan distribution, which are listed in box 4 of Form 1099-R, are claimed as a credit on your return against the taxes you owe; they’re reported as taxes that you’ve already paid for the year.
Items directly reducing income. Personal deductions such as for mortgage interest, state and local taxes, and charitable contributions are allowed only if deductions are itemized on Schedule A, but deductions such as for alimony, capital losses, moving expenses to a new job location, business losses, student loan interest, and IRA and Keogh deductions are deducted from gross income even if itemized deductions are not claimed.