Dr. Cassie McKay and her father Neil McKay are played by Brad Dourif and Fiona Dourif, who are father and daughter in real life. This special situation reflects the family bond between the characters on screen more naturally.
Ned Brower, who plays Nurse Jesse, holds a master's degree in nursing science. After completing his nursing training at the UCLA Santa Monica emergency department, he began working as a full-time pediatric emergency nurse at Children's Hospital Los Angeles.
Taylor Dearden, who plays Dr. Mel King, is Bryan Cranston's daughter. She had her first screen experience alongside her father in the 2010 Breaking Bad episode "No Más." Isa Briones, in the role of Dr. Trinity Santos, is the daughter of actor Jon Jon Briones. Although the character Dr. Javadi is referred to as a "nepo baby" in the series, Shabana Azeez does not come from a family in the entertainment industry. By contrast, many actors such as Taylor Dearden, Isa Briones and Fiona Dourif draw attention as the children of well-known names.
The mother of Patrick Ball, who plays Dr. Frank Langdon, was an emergency room nurse, and his father was a paramedic. This family background may have helped him gain insight into the medical world and his character.
Despite playing the youngest character in the main cast, Shabana Azeez was in her late twenties during the first season's filming and was older than her co-stars Supriya Ganesh and Isa Briones.
The series is one of the rare productions to feature Filipino nurses as main or recurring characters. Amielynn Abellera, Kristin Villanueva, Isa Briones and Matt Mercurio are of Filipino origin, and their characters are portrayed as such. Additionally, the character Perlah, played by Abellera, follows Islam, based on her headscarf. Only 10% of the Philippines' population is Muslim in a predominantly Christian country; Islam reached these lands in the 14th century with traders and missionaries, leaving a significant legacy before Spanish colonization.
Ambar Martinez, in the role of Nurse Kim Tate, and Jamie Watkins, in the role of Nurse Jamie Watkins, also work as nurses in real life. In this way, they bring a professional naturalness to their characters.
Shawn Hatosy had appeared in the 2006 ER episode "Jigsaw" as a patient with multiple personality disorder. This experience may have brought a different perspective to his doctor role in The Pitt.
Amielynn Abellera, who plays Nurse Perlah Alawi, was born and raised in Stockton, California. She earned a bachelor's degree in Psychobiology from Santa Clara University and a master's degree in Acting from the University of Southern California.
Katherine LaNasa had played Janet Wilco, a flirtatious mother, in the 2002 ER episode "Walk Like a Man." This role is remembered as one of the early examples of her versatile acting.
Dr. Trinity Santos (Isa Briones) calls Dr. Dennis Whittaker (Gerran Howell) "Huckleberry," or "Fuckleberry" when she's angry, in a mocking but increasingly playful tone. This nickname comes from Whittaker having grown up on a farm in a small Nebraska town, a polite and naive country boy. Inspired by the protagonist of Mark Twain's classic novel The Adventures of Huckleberry Finn, this name emphasizes Whittaker's polite, slightly naive and unworldly farm-boy manner, and Santos's tough, competitive and urban-girl image.