The shop worker had hoped Egypt’s appeal court would accept she could not have known the medicine was illegal in the country, but judges in Cairo upheld her conviction and jail term, The Sun reported.
Ms Plummer, from Hull, told the newspaper: “I thought the appeal judges would see sense and realise I couldn’t have known the tablets were banned. It’s just so absurd.”
The Briton was arrested at the airport when she flew into the Red Sea resort on 9 October last year.
She claimed she was taking the tablets – which are legal in the UK but banned in Egypt – for her Egyptian partner Omar Caboo, who suffers from severe back pain.
Ms Plummer said a colleague who no longer needed the painkillers had given them to her and she had no way of knowing they were illegal in Egypt.
According to her family, she was forced to confess to smuggling by signing paperwork in Arabic, a language she neither reads nor understands.
Appeal judges ruled ignorance of the law was not a defence and found the original court’s decision was correct, the report said.
Ms Plummer’s mother, Roberta Synclair, 64, said: ”We’re disappointed, but not surprised. Each time we come to Egypt we prepare for the worst.”
It was reported earlier this year that Ms Plummer was set to be pardoned by Egypt’s president, but her release never materialised.
A spokesperson for the country’s embassy in the UK later told The Independent the reports had been “fake news”.
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