At the pharmacy I last went to, the medised said 2+ on it but the pharmacist said it was old packaging and it is now 6+. This is not very helpful for an 18month old is it, but I don't think they have changed the product just changed the rules.
think rules have changed, rather than the contents of the bottle. Occasional use to dry up a cold is unlikely to be harmful. Although don't come running down the street after me - i'm not responsible! I gave no advice!