In most cases, you can't deduct
your share of health coverage costs for a group plan offered through your
employer.
The reason? Most premiums are
paid with pre-tax
dollars, which means they are deducted
from your wages before taxes are applied. Deducting them again as a
medical expense would be "double-dipping."
You can only deduct the premiums
if your employer included them in Box 1 (Gross Wages) of your W-2. However,
this is highly unusual and contrary to the standard practice.
Similarly, HSA and MSA
contributions that come out of your paycheck aren't deductible either, as these
contributions are funded with pre-tax dollars.