The "Back in Black" rockers confirmed on the band's official Web site that AC/DC shows in Des Moines, Iowa, Kansas City, Mo., Las Vegas, Louisville, Milwaukee and Phoenix have all been postponed, Rolling Stone magazine reported online Friday.
The band said Johnson, 61, was advised by doctors to rest as the singer recently underwent an unspecified medial procedure.
AC/DC began its Black Ice World Tour in July with a performance in Boston and the tour will resume on Oct. 16 with a show in Washington. New dates for the postponed shows were not reported.
Rolling Stone said AC/DC postponements mark the most recent tour problems for rock bands this year. Multiple medical problems helped disrupt a summer tour by Aerosmith, while Motley Crue and Poison endured health problems and an on-stage accident respectively.