Is it possible to top up IIDB?

I have a case whereby a client gets IIDB and PIP DL standard rate. He has no other adults in the household and no one claim CA for looking after him. Can he claim the SDP and if so can he claim Income Support or ESA which might lead to a health assessment?
Thank you

If he’s incapable of work it would be IR ESA (unless he’s in a UC full service area of course). Otherwise it would be IB JSA. Either should include SDP in his applicable amount.

Thanks a lot for your help