The 'Raise Your Glass' singer was hospitalised late last week after falling seriously ill, but later assured Twitter followers that she is on the road to recovery.
Pink's continuing treatment will force her to miss her headlining slot at an Obama event thrown by leaders of the LGBT community in Los Angeles on Wednesday (June 6).
She will be replaced at the Beverly Wilshire gala by Glee's Darren Criss.
"I'm so bummed I can't perform for The President of the United States this Wed night. Thanx Darren Criss for filling in for me," Pink tweeted.
The star then joked: "Bad timing. Now I've let down my daughter and the President. Wow. Great week. However, Willow just got a Gucci dress and a custom rocking chair for her birthday, plus some Toms (shoes), so it ain't all bad.
"Lucky little girl… I think I got a bag of Cheetos and a teddy bear for my 1st birthday."
Pink's daughter Willow celebrated her 1st birthday on Saturday.
Watch Pink's 'Raise Your Glass' music video below: