Supermarkets do indeed put a block on bulk-buying. I tried to buy some adult paracetamol and some infant calpol (1 carton of each) in the same transaction (my toddler and I both had a virus with a temperature) and I wasn't permitted to do so. They called a supervisor who could see that this wasn't really an excess purchase but I had to pay for them in two transactions. The lady on the till told me that she is instructed not to allow this unless the supervisor says so. So they are trying to make it harder to purchase paracetamol in excess. I feel there should be an advertising campaign informing the public about the dangers of paracetamol OD. So many people imagine that they will gracefully faint, be the centre of attention and be saved in A&E.