The US singer revealed last week that she has fibromyalgia, a chronic illness which can cause pain all over the body.
The 18-city European arm of her “Joanne” tour, which has been postponed until early 2018, was to begin in Barcelona on Thursday, before shows across the continent, including in Milan, Amsterdam, Paris and five in the UK.
Her promoters Live Nation said the agony she was experiencing had “impacted her ability to perform”.
“She remains under the care of expert medical professionals who recommended the postponement earlier today. Lady Gaga is devastated,” Live Nation said in a statement.
“She plans to spend the next seven weeks proactively working with her doctors to heal from this and past traumas that still affect her daily life, and result in severe physical pain in her body,” it said.
Lady Gaga is famous for her spectacular live shows
“She wants to give her fans the best version of the show she built for them when the tour resumes.”
The 31-year-old singer, known for her spectacular live shows, had already cancelled a concert in Rio de Janeiro last week after being hospitalised for “severe pain”.
She also had to pull out of a show in Montreal earlier this month.
On Thursday she told her 70 million followers on Twitter that she was suffering from fibromyalgia, having previously acknowledged living with chronic pain since she was 18.
Last year she disclosed on social media some of the ways she deals with pain, from infrared saunas to ice baths.
The exact causes of fibromyalgia are unknown, though it affects around seven times as many women as men.
It can lead to pain, stiffness and numbness all over the body, induce headaches and migraines, and hamper sleep.
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