Rev. Ingo Dutzmann, pastor of First Lutheran Church of Boston, located blocks from the finish line of the marathon, asked for the "K-9 Comfort Dogs" to be with patients.
The Lutheran Church Charities Comfort Dog program sends dogs and handlers to areas traumatized by disasters.
Dutzmann said his church has been home base for five of the dogs.
The program's philosophy is: "A dog is a friend who brings a calming influence, allowing people to open up their hearts and receive help for what is affecting them."
Some dogs also were taken to visit survivors after the school shootings in Newtown, Conn., and after Hurricane Sandy.
Each comfort dog carries a business card with its name, a Facebook page, Twitter account and an email address.