A British woman who fell ill after drinking contaminated alcohol in Laos has died, the fifth foreign national now suspected to have died in the incident.

British media reported on Thursday that 28-year-old Simone White, a lawyer from southeast London, was among the tourists who died after consuming drinks laced with methanol, a toxic alcohol.

Four other tourists - an Australian, two Danes and an American - have died in the incident in Vang Vieng, a town popular with foreign backpackers.

Bianca Jones, a 19-year-old Australian, also died on Thursday after being taken to a hospital in Thailand on Nov 13.

Police said the amount of methanol in her body was high, leading to swelling of the brain.

Counterfeits of well-known alcohol brands and home-made spirits are a problem in Laos, with the governments of Australia and Britain warning citizens to be cautious when taking drinks there.