All Deng Sha wanted was a rejuvenating treatment on Dec 9 after she felt drained from the rigours of travelling for work.
But the Story Of Yanxi Palace actress, who played the sister of consort Wei Yingluo, now has second-degree burns on her back and arm, she said, after she went for a massage and cupping therapy.
Cupping is a traditional Chinese medicine (TCM) technique that is touted to provide relief for rheumatic pain, neck and shoulder aches and muscle soreness, among other ailments.
Recounting her experiences at an unnamed spa in Beijing in an online post, Chinese actress Deng, 34, also put up photos that show skin scars and blisters, and bandages on her body.
While Deng said the bulk of the injuries are likely to heal, there is a chance that there might be permanent scars in the worst-affected areas.
Cupping has a 2,000-year history, with even American swimming great Michael Phelps seen with the tell-tale red skin marks - after the treatment - at the 2016 Olympic Games in Rio de Janeiro.
In 2011, Taiwanese singer Chyi Chin was hospitalised after he suffered burns in a cupping accident.
The treatment uses a cup that is put rim side down on a chosen body spot after a flame - from an alcohol-soaked cotton wool ball - is inserted inside the cup for about a second.
The idea is to heat up the air in the cup to create a low pressure that allows the cup to "suck" on the skin for between five and 15 minutes.
While cupping is considered safe, TCM experts warn that customers must seek the services of qualified practitioners to avoid skin burns due to dripping alcohol, and skin blisters linked to excessively tight cupping and the cup being left on the body for too long.
Deng did not say how the incident occurred in her case but she provided advice based on what her doctor told her.
"If the flammable substance catches fire while it is on you, use a wet towel to extinguish the fire," she said.
Running cold water over the affected area is also crucial before one seeks help in a hospital.
Deng will know the full extent of her injuries when she goes for a follow-up consultation with her doctor in three weeks.