Adele halted a show to ensure a fan was given medical help.
The chart-topping singer, performing at London's HMV Hammersmith Apollo, stopped the show to allow medics to treat a fan who had fainted.
Adele, who cancelled several shows following her own health problems with a chest infection, was worried about a commotion in the stalls at the start of her song Rumour Has It last night.
The Someone Like You star asked the crowd: "Has someone fainted?"
After she was met with murmurs confirming the incident, she cried "Medic!" into her microphone, before walking to the front of the stage.
Adele stared into the stalls and waited, looking concerned, then asked members of the audience to "stand aside" to allow staff to reach the fan who had been taken ill.
After help arrived, she returned to centre stage and tried to make light of the situation as she told fans: "That's proper rock 'n' roll."
Adele, who has sold three million copies of her latest album 21 so far this year, resumed her tour last week after the cancellations caused by her chest problems.
She is due to perform at the Apollo again tonight and then London's Royal Albert Hall on Thursday.