If you’re new to the party scene, you might wonder why you keep hearing Calvin Klein’s name pop up. No, it’s nothing to do with London Fashion Week, it’s cocaine and ketamine – or CK, if you’re in the know.

While mixing coke and ket may be perplexing to some, many users report feeling euphoric on the combination. Rather than completely cancelling one another out, leaving you bored and sober, coke and ket actually have a synergistic effect, according to harm reduction researcher and director of drugsand.me, Ivan Ezquerra-Romano.

“Cocaine, which stimulates the dopaminergic system in our brains, stimulates the body and makes you feel energetic, confident and euphoric,” says Ezquerra-Romano. “Ketamine, on the other hand, stimulates the glutamatergic system, and has these sensory distortions and elements and spiritual effects but is also an anaesthetic.” Mixing the two means you get the best of both worlds: the weirdness of ketamine and the energy to dance, chat and stay up late.

If you want to try CK, you should know that the best advice we can give you is that if you want to be safe, you shouldn’t do it at all. That said, there are some ways you can stay as safe as possible while mixing coke and ket.

CLEARLY MARK EACH BAG

One of the biggest risks when mixing coke and ket is getting the bags mixed up. Because they’re both white powders, it can be pretty difficult to distinguish between the two, especially if you’re in a dark club or are already a little intoxicated.

This can cause you to redose too much of one or the other, and this can do more than merely mess up your high. “Cocaine increases your heart rate and blood pressure,” says Ezquerra-Romano. “Taking too much can damage your heart and cardiovascular system and, in extreme cases, can lead to seizures.”

Taking too much ketamine, on the other hand, can cause you to K-hole, AKA a sub-anaesthetic state where you completely dissociate from yourself and your surroundings. While some people love a K-hole, it’s important to note that falling into one accidentally might get you into some trouble – you could fall, lose your friends or vomit everywhere. Even if you don’t K-hole, ket makes you clumsy, and it’s still easy to get injured if you take too much.

“Make sure there’s a clear distinction between the two substances,” says Ezquerra-Romano, who recommends either making sure the containers look different or that you clearly mark the bags with a pen. “However you’re using them, make sure that there’s a super easy way to know which one’s which even when you're high,” he adds.

WATCH YOUR DOSE

One of the most common effects of ketamine is that it warps your sense of time and space, meaning it can very quickly become difficult to judge the size of a line or bump and how long it's been since you last dosed, making it easy to overdo it.

“One way to avoid this is to make a note of what you’ve taken and when, such as on a note-taking app on your phone,” says Ezquerra-Romano. “You can also make sure that you have a reference for the size of your lines or bumps, to make sure they don’t change size.” This could be the “width of a note” or something similar, Ezquerra-Romano says. If you’re doing bumps, try marking the point on your key where you’d usually fill it up, or make a note of the features so you can keep track.

SNORT RESPONSIBLY

Coke and ket are usually snorted, and there are a few things you need to keep in mind when snorting drugs.

First: don’t share utensils, whether it’s a note or a straw or something else. “Snorting can damage your nose, and if your blood gets onto the utensil and you share it with someone else – or vice versa – you can really easily transmit diseases [like Hepatitis C],” says Ezquerra-Romano.

Second: try to alternate between both nostrils, so that one doesn’t become more damaged than the other.

Finally: keep your nose hydrated. “Once you’ve finished taking drugs for the night, make sure to clean your nose and hydrate it to help avoid long-term harm.” says Ezquerra-Romano. You can do this by using a nasal spray, cream or just water.

“You may feel you're more coordinated than you actually are, and able to do things you aren’t actually capable of at that point” – Ivan Ezquerra-Romano

TEST YOUR DRUGS

As always, when you’re buying drugs off the black market, you can never be fully sure of what’s in there, even if you’ve used the same dealer for years. “Both of the drugs might be mixed with different cutting agents, so it’s important to test the powders with a Reagent Testing Kit or, if you’re at a festival with drug testing facilities, you can go there.” This way you can make sure you’re not taking too much of something nasty.

DON’T MIX WITH ALCOHOL

Mixing cocaine with alcohol can be potentially fatal, because the combination of cocaine and ethanol in the liver creates a substance that increases toxicity to the heart, liver, and other major organs. Meanwhile, alcohol is a dissociative, so mixing it with ketamine can cause you to feel more “wobbly and uncoordinated” as well as nauseous, says Ezquerra-Romano.

If you’re going to try CK, it's better not to drink any alcohol at all and, if you do, just have one or two before switching to water.

DON’T GET COCKY

Finally, as we’ve noted, ket makes you clumsy and uncoordinated while coke makes you almost sickeningly confident. “You may feel you’re more coordinated than you actually are, and able to do things you aren’t actually capable of at that point,” says Ezquerra-Romano. That false sense of confidence can cause you to get injured, so it’s important to remember what you’ve taken and try your best to make logical decisions, lest you end up tumbling head-first down a flight of stairs.

Stay safe, kids.

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