Laura Plummer, 33, was sentenced to three years in prison in Egypt for smuggling the painkiller which is banned in the country.
Her mother Roberta Sinclair says Plummer has been unexpectedly transferred to Qena prison.
Plummer, from Hull, was being held in the Red Sea resort of Hurghada, where she was arrested at the airport on October 9.
She was arrested after she was found to be carrying 290 tramadol tablets in her suitcase, a painkiller which is legal in the UK but which is banned in Egypt.
Her family said she was taking the tablets for her Egyptian partner Omar Caboo, who suffers from severe back pain and had no idea what she was doing was wrong.
Her sister, Rachel Plummer, confirmed that she had been jailed for three years by a judge when she appeared in court on Tuesday.
She said she did not know the details of a trial had taken place and why the decision had been taken.
Rachel said her mother had travelled out to Egypt for the hearing and was “devastated” by the sentence.
The Plummer family has previously said the 33-year-old had no idea that what she doing was illegal and was just “daft”.
They said she did not try to hide the medicine, which she had been given by a friend, and she thought it was a joke when she was pulled over by officials after arriving for a holiday with her partner.
In a TV interview last month, Mrs Sinclair said her daughter was being held in terrible conditions in a communal cell with no beds, sharing with up to 25 other women.
Her family had been told that she could face up to 25 years in jail, with one lawyer even mentioning the death penalty.