Dudley Moore as Dr. Jack Hammond / Chris Hammond

Kirk Cameron as Chris Hammond / Dr. Jack Hammond

Margaret Colin as Ginnie Armbruster

Catherine Hicks as Dr. Amy Larkin

Patrick O'Neal as Dr. Larry Armbruster

Sean Astin as Clarence / Trigger

Camille Cooper as Lori Beaumont

Micah Grant as Rick Anderson, Lori's Boyfriend

Bill Morrison as Trigger's Uncle Earl

Skeeter Vaughan as Medicine Man

Larry Sellers as Navajo Helper

Tami David as Navajo Girl

Maxine Stuart as Phyllis, Hammonds' Housekeeper

David Wohl as Dr. Roger Hartwood

Michael Horton as Dr. Mike O'Donald

Randy Lowell as Dr. Spellner

Art Frankel as Mr. Racine, Heart Patient

Christine Healy as Hospital Administrator

Mary Jane Courier as Operating Nurse

Debbie Zipp as Nurse with Dying Patient

Teresa Bowman as Nurse with Heart Patient

Brian Peck as Intern with Heart Patient

Carol Swarbrick as Norma, Hospital Secretary

Kedric Wolfe as Sidney, Board Member

Robert Balderson as Hal Gilden, Board Member

Dakin Matthews as Old Man Morrison

Les Lannom as Coach Ellis

Lorna Hill as Mrs. Davis

John Stinson as Math Teacher

Bill Stevenson as Biology Student

Alexandra Kenworthy as Janice Stenfield, College Interviewer

Jamison Selby as Rick's Friend

Lloyd Nelson as Teacher in Hall

John Tokatlian as Student

Mark McCannon as Student

Jan Duncan as Student

Armin Shimerman as Trigger's Dad

Kitty Swink as Trigger's Mom

Lisa Robins as Bartender

James Lashly as Freemont, Corky's Man

Corki Grazer as Corky, Woman in Labor

Nancy Lenehan as Waitress in Desert Diner

Richard Gonzales as Paper Boy (as Richard Gilberts)