Continuity mistake: When the fight in the apartment occurs Victor is choking Eddie. At the start of the scene the dish sponge he eventually shoved in Victor's mouth is resting beside the sink. When the camera angle changes the sponge is in the sink. When Eddie grabs the sponge it's next to the sink again. (01:20:52)
Plot hole: If Bradley Cooper was able to "quintuple" his money every day in the market as he claims to have done, he would have been able to earn the $100k he borrowed from a loan shark within a few days, starting from $800. Alternatively, he is shown in one scene winning a pot in poker where he could presumably also make a large amount of "seed" money from gambling. There was no need to borrow such a small sum of money from a loan shark, making the entire sub-plot unnecessary.
Continuity mistake: When Eddie is hiding with the golf club, there is a blue chair which got knocked over during the murder. But a few minutes later when Eddie is peeking round the corner to check for intruders, the blue chair is magically standing upright again.
Continuity mistake: When Eddie is eating breakfast and waiting for Van Loon, his hands and the food he is holding change position repeatedly between shots; sometimes his hands are down, sometimes they are holding up some food, and the amount of food he his holding changes too.
Character mistake: In the Italian restaurant, Eddie is speaking jibberish, not Italian at all.
Suggested correction: He is speaking Italian.
I am Italian. He is speaking gibberish.
Factual error: Immediately after Eddie surfaces following his dive, he rests with his head well above the water. Had he actually been in water deep enough for the dive, he would have floated with his chin about even with the surface.
Factual error: Eddie claims it takes 30s for the drug to take effect. Tablets/capsules do not work within 30 seconds after ingestion. At most, 15mins is the time a drug can be absorbed into the body. This is also noted in the movie reviews.
Factual error: During the shootout in the apartment, the blinded henchman fires his handgun 24 times before reloading (and about the same afterwards). Only small-calibre pistols would have that capacity, and the gun he's using isn't one (either to look at and from the bullet holes it causes).
Continuity mistake: At the beginning of the movie, when the shot pans up the front of Eddie's building from street level, there is a balcony a few levels before we reach the top. When Eddie looks down from where he is standing and we see the front of the building from his point of view, the balcony is no longer there; the front of the building is now completely flat.
Other mistake: When Eddie leaves his soon-to-be murdered friend's apartment, the apartment door automatically closes behind him. However, when Eddie returns, the door is ajar. It wouldn't be ajar if it were an automatically closing door.
Deliberate mistake: Eddie is reported in the newspaper as being a mystery trader getting incredible returns. By whom? He is using an online account, so not a broker who can blab to others. The brokerage would not say anything or they would face massive privacy breach fines from the SEC.
Plot hole: NZT makes Eddie hyper-aware of everything and allows him to access all memories in his brain, so he is able to make highly intelligent decisions and outsmart others. He somehow fails to realise how reckless he is being when he originally makes over $2 million in the stock market (and also wins at the casino) and the attention it would draw to him. He made himself a huge target for others, some of whom would know he was on NZT, but somehow was clueless about this while being aware of everything else.
Continuity mistake: In the restaurant scene at the end of the movie Eddie's flag lapel pin is right side up. The camera cuts to the waiter and when it cuts back to Eddie the flag pin is upside down.
Continuity mistake: Before Eddie dives in to the sea, the sunshine is indicative of midday, but when he is swimming it's more like evening.
Revealing mistake: After Eddie's big dive, as he resurfaces there is a reflection of the water that can be seen above the waterline (on the camera lens).
Suggested correction: The main character says he did quintuple his money four days in a row, not that he could continue to do so. "Presumably" he could do anything, like robbing a bank. Gambling is not a secure source of income, even with knowledge of the odds and every tell, he could also lose a lot of money.
He takes the seed money and then goes on to make a couple million with it on the stock market. There's really no reason he couldn't have just done that with the $800 seed money (also what the hell happened to that $10-20k stack of cash he took from Vernon's apartment? Somehow that was dwindled down to only $800?). The time constraint was totally artificial. He didn't need to conquer the world in 2 months except for the needs of the plot.