My GP & HV have said I'm OK to take 30/500 Co-codamol while BF along with 400 Ibuprofen (all of which is to manage deep breast thrush pain).
I suffer with the traditional constipation if I don't eat loads of fruit and veg but DD has always been fine.
Agree that it's best to check the info sheet in the pack of tablets though as each type is different.