What do you mean "on my behalf"?
If your employer pays your health insurance as part of your salary package, then Windup's advice is correct.
However, if your employer just facilitates your payment of the health insurance as a salary deduction (e.g. to avail of some kind of group discount), then no further action is required as you'll have all ready obtained the tax relief at source (by paying, say, €800 when the gross premium is actually, say, €1,000).