You don't. That is not deductible.
From IRS Pub. 502 under expenses that you can not deduct:
"The part of your car insurance that provides medical insurance coverage for all persons injured in or by your car because the part of the premium providing insurance for you, your spouse, and your dependents isn't stated separately from the part of the premium providing insurance for medical care for others."
IRS Pub. 502,
http://www.irs.gov/pub/irs-pdf/p502.pdf