Trivia

Sidney James spent most of his screen time in bed, as he had recently suffered a heart attack.

The majority of the scenes between Joan Sims and Frankie Howerd in the private ward had to be shot separately and edited together because Sims couldn't look at Howerd without corpsing.

Contains a sly reference to Carry on Nurse (1959), specifically the daffodil thermometer scene. When a nurse approaches Francis Bigger with a daffodil, he says, "Oh no you don't! I saw that film!"

Despite their respective ninth and tenth billings, Hattie Jacques and Anita Harris are the two most prominently featured female players in the cast. Barbara Windsor, making only her second appearance in the series, was the highest billed female star but has a somewhat under-written role, her character serving mainly to further the plot, and who is entirely absent for the final third of the film.

Kenneth Williams originally turned down the role of Dr Tinkle and was given Francis Bigger, but found fault with the role and returned to the Tinkle character.