It is not shown how did Ray get rid of handcuffs.
During the flashback scene outside White Castle, the acid-buying complainer is shown running along a street and then entering a cab. The street has red colored crosswalks (or bicycle paths) and the cab is green and white. Neither the red path nor any green and white cabs are found in New York City, let alone the Queens, New York area where the film takes place.
The movie's plot is supposed to take place during one night. But towards the end, the news broadcaster says "Now an update on last week's bank robbery in Flushing."
No medical doctor would put butterfly stitches, aka steristrips, on a patient's cheek as the muscles would pull too hard on them when speaking, laughing, eating, etc.
The butterfly stitches, aka steristrips, obviously do not pull on the wounds' margins (edges) on Nick's face revealing it is make-up.
One can clearly hear a ventilator machine "breathing" in the black elderly patient's room where Connie is hiding and yet no one is ventilated.
When the getaway car hits a parked car, that car and the one in the front of it just roll away revealing that they are not in the Park position.
Whether a patient is unconscious because of drugs or a head trauma, they should not be left on their back without being put into a coma and intubated as they are at high risk of suffocating (unless an antidote can be administered in the case of drug overdose).
Connie should have peroxided his dark hair first before being able to dye it blonde.
The employees at the pizza restaurant were credited as "Pizza Hut" before their job titles during the End Credits, when clearly it was Domino's Pizza where the scene took place.
When Connie goes to the hospital to see his brother and is walking down the hall on the 6th floor, individuals are seen in the reflection of the glass.
Crew visible in reflection of furniture when Ray enters the apartment at the 1 hr 23 minute mark.
When Connie drives past the Elmhurst Hospital to drop off Ray, he is actually driving past the Saint Joseph's Medical Center in Yonkers, New York.
It was the Nassau County Police department that showed up at the Adventureland Amusement Park. However, Adventureland is located in East Farmingdale in Suffolk County.
They're at Adventureland amusement park in the early morning hours, but the digital clock on the monitor from the security camera says it's 08:34 pm.
The main character asks a driver to take him to Queens, specifically Queens Blvd. near "the Union Turnpike". No one from NYC would ever refer to Union Turnpike as the Union Turnpike.
Connie does not take another few minutes to look for the money after the cops' departure from the park.
It is very risky to restrain an unconscious patient without active medical monitoring.