Prescription drug coverage for Medicaid?

Hello all,

Following up on my FIL in NC... After 3 long weeks of work, he is now on Medicaid and in an ALF. But they are telling his family that he needs to have a prescription drug plan, such as Medicare Part D (I presume). The problem is, neither he nor MIL (she is still alive) *ever* had Part D. My wife looked into it about a year ago, when he needed some expensive medicine, but the "catch up" costs because he never had it would have been worse than paying for the medicine!

Can anyone enlighten me about what it means to both be on Medicaid *and* have some type of prescription drug plan?

Thanks!

Bood