Laura Plummer, 33, a shop worker from Hull, was sentenced on Boxing Day, nearly three months after she was found to be carrying 290 tramadol tablets in her suitcase.
The painkiller is legal in the UK, but banned in Egypt.
The court was told 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.
Ms Plummer's sister, Rachel, said their mother, Roberta Synclair, was in court for the "devastating" judgment and had to watch as her daughter was taken away sobbing in a "cage".
Rachel said her mother had been told Ms Plummer would be held in police cells so she could visit her and take vital supplies.
But Ms Synclair travelled to the cells on Wednesday only to find her daughter had already been transferred to a prison in Qena.
Rachel said the prison in Qena is known to be a very difficult place to be. She said: "No prisons are nice but I think Qena's the bad one, which is terrifying for us because we fear for her so much.
"She's just not cut-out to be in a prison, even in a UK prison never mind a prison abroad."
But she said reports her sister had been attacked in prison were not true.
In a TV interview last month, Ms Sinclair said her daughter was being held in terrible conditions in a communal cell with no beds, sharing with up to 25 other women.
Ms Plummer was arrested on October 9 when she flew into the Red Sea resort of Hurghada, where she was arrested at the airport on 9 October.
Her family had been told that she could face up to 25 years in jail, with one lawyer even mentioning the death penalty.
On Tuesday, Ms Plummer's local MP, Karl Turner, said he had spoken to her defence lawyer in Egypt who said she had 60 days to launch an appeal and he expected she will.
Additional reporting by Press Association
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