Blooper

When Kumail is eating fast food and receives a text saying that he is supposed to be on stage in 20 minutes, the text is marked as being sent 1 day beforehand.

In the opening scene at the Comedy Club, Mary is seen doing part of her set. When she comes backstage where the men are, she is wearing a different outfit, and her hairstyle has changed.

Early in the film, Kumail throws a photograph on the pile of pictures in his cigar box. Below several other pictures is a photograph of a woman in a light blue hijab. Later in the film, he again throws a photograph on the pile; it is the same picture of the woman in the light blue hijab.

When Kumail doesn't show up to dinner, his brother Naveed claims to have called him multiple times. Later on, Kumail checks his phone to see several missed calls from his mother and none from Naveed.

Near the end of the movie when Kumail is looking through the window in the hospital room door, he can see Emily's head, but when the shot switches to the other side of the bed, it is obvious that she couldn't be seen from the window because of the angle of the bathroom wall.

The ED doctor goes to Kumail in a panic, asking him to sign the documentation to intubate Emily but she is an adult and fully conscious so she should be the one making the informed decision.

Kumail tells Emily that L'abominevole Dr. Phibes (1971) was made in 1969 by MGM. The film was released by American International in 1971.

However, this is not a factual mistake but rather an approximation by the character.

The ED doctor tells Kumail they need to intubate Emily straight away and yet she is not showing any signs of respiratory distress or increased work of breathing.

The ECG monitoring reads 106 bpm (beats per minute), which is a sign of distress, but the "line" is much slower (around 60), which shows that the patient is indeed stabilized by the induced coma and the artificial ventilation (and is probably the actress's real heart rate).

The scene where Emily says she wants to go to a coffee shop has a digital clock where the time moves back and forth.

When Holly Hunter is signing papers to discharge her daughter from the hospital, she checks the time on her watch by looking at the bottom of her wrist. However, the face of the watch is on the top of her wrist, so she wouldn't be able to see the time.

On the marketing image that shows all the characters, movie title etc, it shows Kumail's mother wearing a hospital visitors pass. She never went to the hospital.

When Kumail is eating pizza with Emily's parents they are not eating either of the two very common styles of Chicago Pizza. They appear to be eating a New York style pizza.

Although the film is set in Chicago and Emily is said to be at "City View Hospital", a sign for Katz Women's Hospital at the Long Island Jewish Medical Center in New York is visible when Kumail arrives.

Although he lives in Chicago, Kumail's car has a New York inspection sticker on the windshield.

The ED doctor tells Kumail they need to intubate Emily straight away and yet no one has given her any oxygen (through a nasal tube first, then a mask, then a non-rebreather) to see how she would respond to this simple treatment.

If indeed Emily was supposed to have a very bad flu and the doctors first dealt with a likely infection, she should have been in an isolation negative-pressure room available in all emergency departments.