My son is 19 and has the same problem - though has turned more to acne now. He has tried various lotions and potions - some clear them up, but they come back again.
Freedom Gel - Avon Clear Skin Blemish Cream - these have been the most successful ones he has used. At the moment I have him trying Decleor Prolagene Gel (this is more for scrarring etc).
The only time they truly clear up is when he goes on holiday abroad or skiing.
Has she been to the GP - my son did and they wanted to put him on a course of antibiotics, for around 6 months or longer - I did'nt think this was a good idea, so he did'nt go down that route.
Good luck - and if you find a miracle cream, let me know !!
Bye
Denise