The Foreign Office did not release details of specific incidents in any of the new countries on the warning list.
But Morgan, a Briton who contacted BBC Newsbeat about a recent visit to Japan, said her experience in bars there suggested tourists were unaware of the potential risks.
“The offering would be ‘come and take a free shot with me – we’ve got tequila, we’ve got vodka’,” she said.
“Obviously, you are taking their word for it. It’s quite dangerous in that sense. There were loads of other tourists just taking the shots, just drinking, not seeing where the bottle was from.”
Last month campaigners and the families of some of the Britons who have died or been injured from methanol poisoning abroad met members of the travel industry and MPs in parliament.
Among them was Calum Macdonald, who had been backpacking in Laos when he fell victim to methanol poisoning in Vang Vieng and went blind.
The 23-year-old from Sunbury-on-Thames said: “I think it’s important that people know, obviously, because it’s quite a simple bit of information you can get that can really save you a lot of pain.
“I certainly think if I’d been aware of the risks I wouldn’t be here today without my vision.”
Hamish Falconer, the Foreign Office minister responsible for consular and crisis, said: “Methanol poisoning can kill. It can be difficult to detect when drinking and early symptoms mirror ordinary alcohol poisoning. By the time travellers realise the danger, it can be too late.”
He added: “No family should endure what the campaigners’ families have suffered. Their determination to prevent others facing the same tragedy has been instrumental in driving forward these vital updates to our travel advice.”
