But morning-after expatriates in Canada are being denied the fizzy drink thanks to a rogue ingredient.
It contains a red food colouring, Ponceau 4R, which could cause hyperactivity in children and has been declared illegal by the Canadian Food Inspection Agency.
The body has written to the owner of a British foods speciality shop, in Saskatoon, Saskatchewan, telling him products such as Irn-Bru, Marmite, Ovaltine, Lucozade, Penguin biscuits and Bovril “are enriched with vitamins and minerals” and therefore illegal.
The letter to Tony Badger, who has sold the items in his three stores since 1997 also said some canned soups and stocks had too high a content of animal products.
Mr Badger said: “We have been bringing Irn-Bru over here since we opened, and my understanding was that we were importing legally.
“We declared it through a customs broker and have never had an issue until now.”
The shopkeeper began having trouble in October when his Christmas shipment was detained, and he began to questions why the process took longer than usual.
He was told that some of his products did not meet Canadian standards and, in order to have the legal products released, he had to abandon the seized ones.
What was left of the shipment finally arrived on December 18, but Mr Badger still has not received a list of the seized products.
CFIA officials arrived at his store last week and seized the remaining products from his shelves. Customer Brian Smith, who regularly buys Ovaltine and Royal Game soup, both of which were removed said: “I can feel for Tony, because it’s unfair.
“He has been in business since 1997, and now they are stopping his goods.
“If they are good enough for the UK, they should be good enough for Canada.”
A spokesman for Irn-Bru makers AG Barr said the company produces a Canada-specific version in a specially labelled 500ml plastic bottle.
It does not contain Ponceau 4R and has been exported via a local distributor for more than 15 years.
It is the only Irn-Bru product AG Barr exports to Canada, according to the spokesman.
But Mr Badger said all the British speciality shops and grocery stores he knows of that sell Irn-Bru are selling the British recipe.
Barrs is working to replace the food colouring to bring the product in line with the new guidelines set by the Food Standards Agency.
The company assures the public the colouring is safe, but all products with Ponceau 4R (E124) must carry a warning label stating it could cause hyperactivity in children.
Scots broadcaster Dominik Diamond, who now presents the morning show on Radio 96.5 in Halifax, Nova Scotia, said: “I have had Irn-Bru all over Canada since I moved here.
“Within five minutes of meeting a fellow Scot here, they will tell you where you can buy the Bru.
“It is so popular they will not be able to stop expats drinking it.
“We will just have to resort to smuggling it in just like we do with roll and sausage.” spy other phone