The singer-songwriter, who ate the deadly webcap mushrooms along with her husband Nicholas Evans, author of The Horse Whisperer, her brother Sir Alastair Gordon Cumming and his wife, is performing a benefit concert in London on November 15 in aid of the charity Give a Kidney.
The charity aims to raise awareness of altruistic kidney donation – a living person donating a kidney to someone they do not know with kidney failure.
Ms Gordon Cumming, who received a kidney from a live donor three months ago, said: "There are so many people who would say 'I'd do it for my relations but for a stranger? I don't think so.' I understand that, of course I do, but it is possible to live a perfectly normal life with one kidney.
"There are 7000 people waiting for a kidney in this country. And anything we can do to highlight the situation is worth it."
Ms Gordon Cumming was donated a kidney by the mother of her son's best friend, after being kept alive by dialysis for several years. This will be her first concert since the operation.
She added: "The transplant went very smoothly. I was with my lovely donor, Serena. I was in hospital a week, which was pretty good going, and Serena was out in three days.
"It's uncomfortable and you're dealing with a large scar, but you wake up from it with a very positive feeling. Mainly, you just think 'Wow, no more dialysis'."
Ms Gordon Cumming also revealed her husband, who received a kidney from his daughter last year, had never been back to Altyre – her family's estate in Moray where the group ate the mushrooms. She added: "I hope he will go back one day. A couple of years ago I went back to face it."
Ms Gordon Cumming's call for kidneys comes as a new organ donation campaign is launched as more than 40% of Scots have now signed up to the NHS Organ Donor Register.
This year's campaign has been designed to get people talking about donation.