Last week, police in the English seaside town of Eastbourne warned that they had seized some 100 percent pure cocaine. As in: legitimately pure stuff. Not the "trust me, mate – this shit bangs" pub-grub that's actually only 10 to 40 percent pure, but the kind of pre-cut powder you're much more likely to find in a Peruvian jungle lab than a resort town with literally the oldest population in the UK.

VICE published a short news story about the warning last week and got a bunch of responses to the effect of: "Why is pure cocaine a bad thing?" Turns out that plenty of keyboard critics only read the headline, because the article did explain that higher purity means it's stronger, which means it's more dangerous. Also turns out that a lot of keyboard critics are idiots, because surely you can work that out on your own?

Anyway, for those of you who wanted a more in-depth explanation, I thought I'd speak to a drug expert to see what the difference is between taking the shitty cocaine the UK is used to and the high grade stuff now inexplicably on our streets.

BUYING IT

You're likely to spend anywhere between £50 and £80 for the standard stamped-on rubbish Dale or Samir or "Freddy Flake" shifts from the driver's window of his three-door Astra. But what about the genuine article?

"There's a good chance that low-level street dealers will not know the purity of their cocaine," says neuropharmapsychologist and former government drugs adviser David Nutt. "And it may well be sold at the same price as lower quality cocaine." 

If you're not buying your manufacturing-grade cocaine from an oblivious street dealer, chances are it's made its way to the UK via the dark web. Here, on marketplaces like AlphaBay or Hansa, high grade gak goes for about £70 a gram. That said, if a dealer knows he's got decent gear, by current UK pricing he could charge up to £20 per 0.1 grams.

THE FIRST LINE

"If the cocaine is very dilute, or the user has developed a tolerance, there may be little or no rush," explains Nutt. However, he says, purer coke would give a "surge of peaceful euphoria, alertness and a feeling of power and energy. Users would feel intensely euphoric and afterwards feel super confident and happy, and urgently want to talk, dance, have sex, or otherwise do something with the energy they have."

You know in the YouTube comments for old disco tunes, when you read HustleCruz52 fondly recalling the frankly dangerous amount of blow she used to do before the DEA really got properly up and running? This is what she's on about.

THE SECOND LINE

Because of the high purity, it's unlikely you'll feel the need to do another line within ten minutes of the first, like you might with the teething powder usually on offer in the UK. But bear something in mind: although the positive effects might sound kind of sexy, the negative effects – which Nutt describes as "feeling anxious or impulsive, or finding the urgent rush of energy and raised heart-beat alarming" – would also be exacerbated.

So you may feel fucking great at this point, but equally you also may feel fucking weird and horrible.

THE REST OF THE NIGHT

This is where the strength of higher percentage cocaine really comes into play, and by "comes into play" I mean: has a high chance of stopping and / or seriously damaging your heart.

"Cocaine is a vasoconstrictor, and the majority of coke-related hospital admissions are cardiac issues," says Nutt. "As purity increases, so does your risk of heart damage and overdose. The increased risk would likely be related to acute heart damage or overdose, rather than dependency, which is a chronic consideration, versus high purity on any given night."

So basically: because most British coke users are used to shitty coke, the threat of overdosing becomes very real by the third or fourth line – if, that is, they're done at the same size and regularity as normal.

THE COMEDOWN

So there's semi-good news and some actually quite bad news here. The actually quite bad news is that your top notch cocaine comedown is generally going to feel pretty awful.

"When the chemical is cleared from the body and the brain tries to recover its chemical balance, this is the 'comedown', where the user feels washed out, glum or grumpy, anxious or paranoid," says Nutt – and the more chemicals cleared out, the more that need replacing. "Some users struggle to resist taking more cocaine to delay the inevitable comedown," Nutt adds.

So you're going to feel a bit spooky the next day. The semi-good news? "High purity coke would obviously contain fewer contaminants and cutting agents," says Nutt, of the extra side effects such cutting agents could potentially have – though adds that, really, they're not the primary concern: "Although harm from cutting agents has certainly been documented in cocaine and other drugs – see PMA in ecstasy pills, for example – cocaine dosing is the main issue here."

So on the one hand, your high grade cocaine will probably make you feel like shit, but on the plus side, because it hasn't been absolutely packed with baby laxative, speed or levamisole – a worming agent used on farm animals that's been doing the rounds in Great British Gear – your body might not end up eating itself alive.

Either way, if you are going to use cocaine, there are a few steps you can take to make sure you're using it as safely as possible: crush it up as finely as it will go, alternate your snorting nostril, wait until the effects of each line are over before taking your next, and wash your nose out well at the end of the night.

(This article originally appeared on vice.com and was written by Tom Usher)