During filming, Robin Williams and the rest of the cast and crew worked closely with the Make-A-Wish Foundation to fulfill the fantasies of several children who were at the time undergoing cancer treatment. The children appeared with Williams in scenes at the pediatric ward.
One of the film's producers, Mike Farrell, met the real Patch Adams when Adams served as an advisor to the TV series M*A*S*H (1972), in which Farrell played B.J. Hunnicutt, one of the Army doctors.
Patch Adams said that whenever the film's production would get stressful, Robin Williams would improvise a comedy set to make the cast and crew laugh.
Filmed partially at the University of North Carolina. Robin Williams did stand up comedy for some classes that were in session while filming.
In 2014, co-stars Philip Seymour Hoffman and Robin Williams died within nearly six months of each other. Hoffman died on February 2nd, and Williams died on August 11th.
Patch Adams: The real Patch Adams appears in the scene where the medical school staff returns with the verdict. He sits right behind Robin Williams.