Minnelli, 64, recently released a statement through her publicist saying she has cancelled the performances on the orders of her doctor.
According to Access Hollywood, she said: 'I'm greatly disappointed that I will not be able to continue my tour. I do not want to let down my fans. I will be back on stage on November 20.'
She will now not be performing at an October 15 concert in Spokane, Wash. or a show in Appleton, Wis.
Minnelli has also had to pull out of shows in Illinois, Indiana, Massachusetts and Tennessee.