He's probably best off going to the doctor, as if it's really bad he might get some medicine on prescription. Other than that a chemist should be able to help you out.
go to the doctors, most of the stuff available in chemists are probably not strong enough, also my friend suffered with it, and found that sunlight was very good, so two weeks in a hot sunny place is just the remedy, well if only temporary
i have two grandchildren both had bad acne.
we all know it is a part of being a teenager for some but nowadays can be at least controlled.
our doc gave them antibiotics and although they still have a little they are mostly clear so yes see the doc.
he also said that he regards acne as a mild mental illness
because it affected their confidence, especially my granddaughter.
so, dont waste your money on fancy creams that dont work.
hope it subsides.