DS sore fingernail - ingrowing?

[Morven11]

DS bites his fingernails. I know they do and somehow they get away with it but this time, he thinks it's gone a bit too far because one finger is now really sore. Where what's left of the nail is digging into the skin, a bit greenish.
He's put a bandage round it -

I've suggested the practice nurse - and of course that he finally stops biting his nails. But I wonder if there's an ointment or something at least that might ease the soreness for now? Thanks.

Magnesium sulphate paste is good for "drawing out" pus or a warm compress.

DS1 had a slightly ingrowing toenail and the pharmacist suggested Daktarin in case of infection. It seems to have helped.

If you've already got an appt with the nurse, how about a standard antiseptic cream?

Many thanks, bright and Blue - am going to look at these options carefully. Thanks!