How to express "a little bit of" a mass noun outside of the nominative or accusative case

Question

How do you say "a little (small amount) of" a mass noun when the noun phrase is not in the nominative or accusative case or is the object of a preposition?

Normally a partitive genitive is used, e.g. paulum aquae = a little water, but this construction is allowed with neuter pronouns and adjectives "only if they are nominative or accusative without a preposition" (Bradley's Arnold Rev. Mountford §295.c). So how would you translate something like the following:

He treated the wound with a little medicine.

Vulnus ___ cūrāvit.

...if *paulō medicāmentī and *per paulum medicāmentī are not acceptable? The same type of problem could apply to other situations besides the instrumental ablative.

Answer 1

You use paulus adjectively, that is to say:

Vulnus paulo medicamento curavit.

The edition of Bradley's Arnold I found online made this clear by giving the example "Tanto sanguine, not tanto sanguinis".