8 Things Movies Always Get Wrong About Drugs

8. Everyone On Drugs Has Massive Pupils

Possibly one of the most infamous drug movies out there, Requiem for a Dream does a stunning job of demonstrating the levels of f*ck-uppery that shooting a load of Colombia's finest into your bloodstream precipitates. If there were ever a Don't Do Drugs campaign that your teenagers would actually want to watch, it's Requiem.

They do, however, get the pupils wrong.

During the stylish shooting-up sequences, the guys' pupils dilate dramatically, regardless of which particular substance they're abusing. We all vaguely know that if somebody has massive pupils, perhaps coupled with an inclination to tell you long, tedious stories about thier job, then they're probably on something, but it's probably not Heroin.

Opiate class drugs, including Heroin but also Codeine, Methadone and Morphine, actually cause the pupils to constrict to tiny pinpricks. This is because they stimulate the parasympathetic aspect of the autonomic nervous system - that's the bit of your nervous system that controls most of your reflexes.

On the plus side, this makes close-up reading much easier. On the downside, you're high on Heroin and probably not up to cracking on with your summer read.