RubyLu was rescued from Cyprus last month suffering from mammary cancer.
Staff at Glendrick Roost Animal Welfare Centre in Aberfoyle, near Stirling, were told following surgery that nothing except palliative care could be provided for her.
But the centre hopes to extend the Rottweiler-cross’s life by giving her a daily dose of cannabidiol (CBD) oil.
The oil – the active ingredient in cannabis, which is non-psychoactive – was approved for use in humans in 2016, primarily for its anti-convulsant properties.
Mione Morrison, founder of the charity, yesterday posted a photograph of RubyLu, five, captioned: “She is coming along so well. RubyLu has only been with us since the night of 19th February but acts as if she has always been here.
“Her CBD oil has been increased to three drops a day so with that, the turmeric, reiki and the love she is getting here her cancer is being attacked from all sides.”
She added: “Cannabis oil is an alternative to doing nothing to help inhibit Ruby Lu’s grade three mammary cancer.
“Reports are supporting the fact that this oil MAY be able to inhibit the growth of abnormal cells and may even kill cancer cells.”
Ms Morrison said vets removed the tumour and recommended palliative care only.
“This is better than sitting and waiting for it to come back and kill her – definitely worth a try,” she said.
RubyLu arrived at Glendrick Roost on 19 February after flying into Manchester and being transported to Scotland.
Earlier this year, dog owner Steve Watson from Suffolk revealed that CBD oil had changed the life of his severely epileptic dog, Titch.
Last year another pet owner, Marianne Dickson, praised the oil for curing her pooch Honey’s anxiety.
The 44-year-old from Edinburgh said her rescue dog used to cower away from other dogs and was incredibly nervous before starting to get her daily dose of CBD oil.
Government advisers made it legal to buy CBD oil in October 2016 after they admitted that it has a “restoring, correcting or modifying” effect on humans.
Over recent years, many cancer sufferers have spoken out about how CBD oil has helped with their recovery. Cannabidiol has anticonvulsant properties, which some people have said helps reduce seizures in mammals.