Also missing is Sarada Simkhada, a senior nurse at Darent Valley Hospital in Kent.
Her brother Shambhu said that her family was desperately waiting for news of her safety after she lost contact with her relatives while on a pilgrimage to Mount Kailash.
“My dear sister, wherever you are, please stay strong. We are praying for your safety every moment and waiting desperately for you to return home,” he wrote on social media.
A family of four, including an 18-year-old A-Level student and a 13-year-old girl, from Surrey are also among the missing.
Spandan Sahu, 18, was in Nepal with his father Santosh Sahu, 46, his mother Surabhi Manmath Padhy, 44, and sister Syna Kumari Sahu, 13.
Spandan had just finished his A-levels at Royal Grammar School Guildford.
In a statement, a spokesperson for the school said: “It is with great concern that we have been informed that a former student, along with members of his family, have been reported missing in Nepal.
“Whilst we are hoping for positive news, we do not have any further information at this time.
“Our thoughts, love and deepest sympathies are with all of the families and loved ones of anyone affected by this tragedy in Nepal at this incredibly difficult time.”
Vikram Kolagatla, from London, told the BBC he has not heard from his wife, Geetha Reddy, since the flooding hit.
Reddy, who has two daughters aged 12 and 14, had been in Hotel Kailash in Rasuwagadh when the flooding hit.
“We’re not sure what to do. I have two little girls, and their schools are starting next week,” Kolagatla added.
“The kids still don’t believe it. They think she’s stuck in the flood and that she’ll come back. They think she’s stuck somewhere and there’s no mobile network.”