According to the report the shooting schedule of the film and TV show clashed.
As Mad Men's central character Don Draper, Hamm was thought to be essential to the TV show.
Hamm's role as a troubled advertising executive with a dark past has brought him stardom and repeated Emmy Award nominations.
However it has been a rough few weeks for the 44-year-old, who has spent 30 days being treated for alcohol addiction.
And his concerns about the future of his career following the end of Mad Men are said to have contributed to Hamm's worries.
Hamm had the support of his longtime partner, actress-filmmaker Jennifer Westfeldt, in his struggle, publicist Annett Wolf said in a statement as his rehab stay was revealed last Tuesday.
The disclosure, first reported by TMZ, came as the final season of the 1960s-set drama begins April 5 on AMC.
Hamm has been fulfilling his promotional obligations for the TV show since his release from rehab, and has thanked fans for their support.
- The Daily Mail