Olivia Newton-John finds relief from the pain of stage 4 breast cancer with cannabis grown at home by her husband.

The Physical singer was first diagnosed with the disease in 1992, and beat it, but the cancer returned and metasticised to her lower back in 2017.

Now Olivia, 70, is relying on husband John Easterling, a natural health practitioner, to help her overcome the illness again, with the Australian star taking advantage of marijuana's legalisation in California to grow the herbal medicinal remedy on their ranch property outside Los Angeles.

“I decided I would use everything I could to get stronger,” she tells People magazine. “My husband hands me all these herbs every morning and makes me a green algae drink. He grows the (marijuana) plants and makes them into liquid for me. I take drops maybe four to five times a day.”

Olivia admits she was “a little nervous” to use the drug initially, but admits her pain decreased as she took it.

“It has helped incredibly with pain maintenance and sleep," she shares.

Olivia's daughter Chloe has also embraced cannabis culture and runs a weed farm in Oregon, a state where the herb is also legalised.

“It’s an amazing plant, a maligned plant, but it’s helping so many people," the Grease star insists.

In addition to curative natural treatments like cannabis, Olivia has received radiation care at her Olivia Newton-John Cancer and Wellness Centre in Melbourne, Australia, and she keeps up a positive mindset through daily meditation.

“The first time I had breast cancer in 1992, I had a transcendental meditation teacher come and give me a mantra, and Deepak Chopra, who was a friend, gave me a mantra," she recalls. "I pray. I meditate. I manage to find stillness just being in nature or playing with my dog or going down and playing with my little mini horses or chickens. I love animals. I find calmness in that."

Olivia opens up even further about her pathway to wellness in her new memoir, Don't Stop Believin', which will be released on 12 March (19).