The announcement was made just three hours before the 59-year-old actor was due to appear on stage at the King's Theatre in Edinburgh.
Lawson will be replaced for a second night in a row by his understudy, Neil McKinven, after taking medical advice following his sudden departure from the show mid-performance on Monday.
The opening performance had to be abruptly halted after Lawson appeared to forget his lines and then announce that he was feeling faint, before being helped off the stage by two fellow cast members.
Lawson had been performing in a pivotal scene with John Stahl, who plays Rebus’s arch-nemesis Cafferty, and Cathy Tyson, who plays long-time the retired detective’s long-time sidekick Siobhan Clarke. McKinven took over the role of Rebus after a break of around five minutes.
The King’s Theatre was sold out for the opening night of the run of the play, created by author Ian Rankin, who was in the audience, and playwright Rona Munro.
A statement issued on behalf of the show's producers said: "Charles Lawson was unfortunately taken ill towards the end of last night's performance of Rebus: Long Shadows at the King’s Theatre.
"However, in true theatrical fashion, his understudy Neil McKinven went on and completed the performance.
"Doctors have advised that Mr Lawson should not perform this evening and so Neil McKinven will perform the part of Rebus. Mr Lawson will be back on stage as soon as possible."
Long Shadows, which premiered at Birmingham Rep last month, is due to continue its run at the King's until Saturday as part of an extensive UK tour.
It emerged last week that Scottish stage and screen star Andy Gray had pulled out of the forthcoming Christmas panto at the King's Theatre after being diagnosed with blood cancer.The 58-year-old had been due to appear with regular co-stars Grant Stott and Allan Stewart in Beauty and the Beast, but was advised to withdraw from the show from his doctors.