Can I deduct IRMA charges even if my total medical costs are below 7.5? of my AGI? Is this a tax or a medical expense?

Are you referring to the IMRAA surcharge for Medicare?  If so, that charge was included in medical expenses when you reported your social security payment and automatically transferred to Sch A. 

In spite of how it seems to you, the IRMAA amount is an additional premium for Medicare. It's a medical expense, not a tax.

Thank you!  I assumed it was a medical expense but wanted to confirm before filing.