It’s still more than three months until finals, but there’s a whiff of panic in the air of the Edinburgh student flat where I’m having dinner. “Everybody’s feeling it,” says Suzy. Feeling what? “The pressure. There’s just so much pressure.” About what? Your exams? Or what to do next?

“Everything. I shouldn’t even be here. I didn’t even want to go to university but everyone said I should. And the work! It’s just… there’s so much of it! I feel like I wouldn’t even have a chance if it wasn’t for modafinil.”

Modafinil: a prescription-only medication for narcolepsy that the NHS’s website describes as “a central nervous system stimulant” that prevents “excessive sleepiness during daytime hours”. Or, used off-label, bought via some off-shore pharmaceutical retailer, it’s what’s known as a “smart drug”. I hadn’t even heard of it a week ago, but it turns out they’re all on it, the students. They’ve all taken it on at least a couple of occasions, all five of the female final-year students who live in this particular flat, and all five of the male final-year students they’ve invited over to dinner.

“It’s not that it makes you more intelligent,” says Phoebe, a history student. “It’s just that it helps you work. You can study for longer. You don’t get distracted. You’re actually happy to go to the library and you don’t even want to stop for lunch. And then it’s like 7pm, and you’re still, ‘Actually, you know what? I could do another hour.’”

But isn’t it cheating? Or like doping in cycling? If lots of people are doing it, it’s too much of a disadvantage not to join in?

“My ex-girlfriend used to say that to me,” says Johnny, another history student. “She was like, ‘I don’t agree with it. It’s unfair.’ And then when the pressure was on, she was like, ‘Can you give me some?’”

Everyone’s taking it, they say. What do you mean everyone? “Everyone!” says Phoebe. “Everyone I know, anyway. It’s rife.”

You do have to be to be careful though, says Johnny. “It gives you this amazing concentration but you have to make sure you’re actually in front of your books. I spent five hours in my room rearranging my iTunes library on it once.”

The talk moves on, but later when I ask them what they’re going to do next year, they tense up. The ones who do know what they want to do next year worry about how they’re going to get there. And the ones who don’t know just go into a state of mild panic and ask questions like, “How did you know what you wanted to do?”

“My parents don’t have a clue what it’s like these days,” says Daniel. “My dad is really successful. And he got to where he is today with a 2:2 from Hull University. You wouldn’t get a look in the door with most jobs with that these days.”

Student life has changed. But it’s not that it’s changed from what it was like when I was a student a generation ago, it’s that it’s changed from what it was even five years ago. Jack Rivlin, who’s the founder and editor of the Tab, a national network of student news sites, says it’s obvious from the traffic stats on his website.

“We can track it from the change in stories that interest students these days. It’s stories about CVs, jobs, fees… much more so than it used to be. We can see it. Students are much more career-conscious than they were even five years ago when I was a student. They’re much more conscious of getting value out of their degree. The atmosphere is definitely careerist and competitive and getting more so.”

And, this is where modafinil, and the other smart drugs that have become increasingly common in universities across Britain – Ritalin (methylphenidate), Adderall (mixed amphetamine salts), Dexedrine (dextroamphetamine), all of which are attention deficit hyperactivity disorder (ADHD) medications – start to look like a symptom rather than a cause.

Because this year’s final students are the first to graduate into a brave new world of massive debt. They’re the first cohort to come through who will experience the full force of the impact of the coalition’s decision to introduce tuition fees: they’ll owe an average of £44,000 a head by the time they leave in just a few months. This is at a time when stories about graduate unemployment and exploited interns are never far from the news pages – last week a media group admitted that it was charging students to write for it, and before that it was a thinktank making its unpaid interns pay £300 for a reference.

And in this scenario, if you were offered a small white pill that held the promise of enhanced productivity, greater focus, more hours in the library, and, ultimately, the potential of a better degree, well… it’s not hard to see the attraction.

Though, it’s not quite as simple as that. Everyone’s brain chemistry is different. Everyone reacts in a different way. There are no medical checks when you click a button on the internet. And no controls over what you’re actually sent. I hear story after story about essay deadlines achieved against all odds and then when I’m leaving, one of the quieter women says to me: “It’s awful. I just got… very anxious. Depressed.”

There have always been drugs, of course. Every generation has had its narcotic of choice. LSD provided the mind-expanding backdrop to the 60s and the appearance of ecstasy in the late 80s kickstarted rave culture and another summer of love. But this use of drugs to work harder, to gain a competitive advantage, to produce more – this is new, at least in Britain. Anjan Chatterjee, a professor of neurology at the University of Pennsylvania, who has published several influential papers on the ethics of smart drugs, tells me that he sometimes makes jokes about it. “When I was young, students would use drugs to check out. Now they’re using them to check in.”

He’s witnessed the rise, in the last 10 years, of a generation of American students doping themselves up on various medications they believe will give them a competitive edge. “It’s even in high schools now, especially in the more affluent suburbs. Students call them ‘study aids’; they don’t even think of them as drugs. There’s an entire grey market on campuses. But then, the current estimate is that a third of all students have a prescription for some sort of psychoactive medication anyway: antidepressants, or medication for ADHD, or for anxiety, so the availability is quite high. Often, they’ll just sell on the medication in the library.”

He believes that cognitive enhancement – or cosmetic neurology, as he calls it – is likely to become viewed as normal over time, in much the same way as cosmetic surgery has been. If it’s available, people will avail themselves of it. And his intuition “is that this use of drugs is not the cause of this sense of competition. It’s a phenomenon of it.” Smart drugs are part of a “parcel of broader cultural trends” that tap into something that is already within our culture. “And this is what does give me pause. It’s this relentless pursuit of productivity, and material productivity in particular that seems to be at the root of this. Going after drugs is a symptom of that underlying impulse.”

His account of the pattern of use of these drugs tallies with what the students in Edinburgh tell me too. I meet with a smaller group of them the day after our dinner: Phoebe and Johnny from the night before and Annie, who’s studying English, and they talk me through how and when they started taking them. What’s noticeable is that they’re all high performers, all on target for high 2:1s or firsts, academically bright but also articulate and sociable and trying to fit everything in. They’re all working hard while maintaining fairly full-on social lives: a large network of friends, nights out clubbing, nights in having people around for dinner.

“I didn’t know anything about it in my first year,” says Phoebe. “It’s all coming from the international students. It was the American students that we discovered it from. They’re all medicated and they’ve got prescriptions and they sell them on.”

Johnny describes his first experience with Adderall, which he bought off an American student. “It made you feel weird. I remember sitting in an exam and thinking, ‘This is awful.’ And, ‘Oh my God, I feel like I’m going to faint.’ But at that same time I was remembering stuff… I could remember whole paragraphs, word for word. It was amazing.”

It enhanced your memory? “It did. But the whole thing was so unpleasant. And then, last year someone had a prescription for modafinil and started selling them and then we started buying them from a website in Singapore.”

Annie has only taken it when she’s at what she calls “crisis point”. “I had two major essays to deliver within four days of each other and it was such a huge amount of work that I just needed something. And it got me through. I did it. But I have to say my work wasn’t as good as it could have been. It was just quite… shallow. It makes you focus very narrowly and I really zoned in on something which turned out to be quite minor.”

Phoebe has taken such drugs intermittently and lists the plus points: “You take it on an empty stomach first thing in the morning and then you work really hard all day and it kills your appetite and then if you go to the gym, you do a really good workout. So you lose weight, nail your exams, and go hard at the gym all at once.”

If it sounds too good to be true, it probably is. Phoebe gave them up because she didn’t like the side effects. “My stomach,” she says, holding her waist. “It wasn’t good.” Johnny describes how he was taking them every day for several months. “And then over Christmas I realised I was definitely dependent on them. And it wasn’t even that beneficial for my work. It’s just kind of like a feeling inside that I need to take some so I can perform.”

He’s cut down but then he reveals that he’s taken one that morning. “Have you?” asks Phoebe, surprised. There’s no burning deadline for any of them today. They’re happy to sit and chat over lunch. “Just a half,” he says. “It just… you know how the first few hours of the day, you struggle to wake up and get going? You take a modafinil and you’re singing R&B in the kitchen half an hour later. You’re just on it.”

You don’t know what’s actually in those pills you’re ordering over the internet from Singapore, though, do you? “No…” says Johnny slowly. “They’re in blister packs though. You know, they look real.”

Modafinil, which is prescribed in the UK and the US as Provigil, was created in a French laboratory in the late 70s and was licensed for use in the UK as a narcolepsy medication in 2002. In the US, that was extended to include excessive daytime sleepiness and shift work sleep disorder. It apes some of the effects of classic stimulants such as amphetamines but without the classic stimulant side-effects: jitters, anxiety and so on. It’s not considered addictive, but some studies have shown that it appears to increase dopamine in the brain’s reward centre, which has been correlated with addictive behaviours.

And while the side effects of modafinil are considered relatively minor – a headache, most frequently, or stomach upset, or relatively rare, serious skin reactions have occurred in a handful of patients – perhaps the biggest issue is that there simply haven’t been any long-term studies into its effects.

Barbara Sahakian is a leading authority on the effects of smart drugs on the brain and she’s continually making just this point. She’s a professor of clinical neuropsychology at Cambridge University and she was one of the first people to realise that the drugs she was studying in her laboratory, drugs to ameliorate the effects of Alzheimer’s and Parkinson’s, or to enhance the cognition of stroke sufferers, were being used for very different reasons.

“I was over in Florida where I was due to speak on my research and I hadn’t been scheduled until late in the day and I turned to my colleague and said, ‘It’s such a shame I’m so jetlagged.’ And he said, ‘Would you like some of my modafinil?’ It was a drug we used in the lab but I’d never thought of it in any other context and I was totally shocked. And then at the break I started asking other colleagues if they took any of these drugs and one said, ‘Yes, I use Adderall.’ And another was using modafinil and somebody else was taking Ritalin. I was quite amazed. At least half the people around the table were using them.”

She wrote about it for Nature magazine. “And they conducted an online survey and out of 1,400 people who responded, one in five was using something. I mean this is people who are [choosing] to fill in a survey on it, but it was still very surprising.”

There are ways that the drug is useful and could be even more useful, she believes. It’s been shown to improve surgeons’ performances. “They’re like shift workers essentially. They work late into the night and they mainly use caffeine and you get serious tremor with that, which is not ideal. It’s been shown to reduce impulsivity in the sleep-deprived, to improve problem-solving ability. If it reduces accidents in the workplace or bus drivers who fall asleep at the wheel, this has to be a good thing.”

What’s more, some of her most recent work has shown that it increases “task motivation. It motivates you to do the things you’ve been putting off. They become more pleasurable. It makes boring things more interesting. It’s the tax return drug.”

But she’s worried about the increasing number of students who come up to her after she gives talks. “Some of them are quite angry – they don’t want to use the drug but they feel they’ll be at a disadvantage.” More than that though is the lack of proper research into the effects over time.

“We just don’t have any long-term studies. That’s why it’s so inadvisable to use them until that’s done and that’s why I’ve been pushing the government to work with the pharmaceutical industry to do that. The other thing with young people is that their brains are still in development. If you have severe ADHD then you need a treatment like Ritalin to be able to function, but if you are a healthy young person… and you are putting these drugs into a developing brain. Well, we just don’t know enough about what this does.”

In the absence of hard facts, there are stories. I email back and forth with a young woman in New York called Kate Miller, who wrote a gripping account of her life on, and coming off, Adderall for the New York Times. Of how she discovered it in her final year at university and continued to use it as she started in a junior position at a law firm doing 60-hour weeks, until she finally realised she had become dependent and quit. Her withdrawal was long and difficult: “I slept through appointments and was unable to stay up to meet deadlines. The drug had curbed my appetite and… without it I was ravenous.” She found she was “sensitive and emotional from the new chemical imbalance” and “gaining weight and falling behind at work” only exacerbated it.

But the person I most want to speak to about his experience of taking smart drugs won’t talk to me about it: Johann Hari. He was a prolific and well-regarded columnist for the Independent until his career was consumed by a media firestorm in 2011. It was revealed that he’d written interviews with people that contained quotes he’d lifted from other sources and that he’d made malevolent remarks, pseudonymously, on other journalists’ Wikipedia pages.

Before that though, in 2008, he’d written an article about modafinil that extolled its unique and wondrous properties.

“Normally, one day out of seven I have a day when I’m working at my best – I’ve slept really well and everything comes easily and fast. Provigil makes every day into that kind of day,” he wrote. It enabled him to “glide into a state of concentration – deep, cool, effortless concentration”. And the upshot is that he “inhales books” and “exhales articles” effortlessly.

Eventually, though, he concludes that “taking narcolepsy drugs when you don’t have narcolepsy is just stupid”. And he cuts a deal with himself. He’ll put away the “gorgeous temptress” Provigil and only take it when “I’m really knackered” and not “more than two or three a month”.

Except that wasn’t it. He didn’t throw off the gorgeous temptress. He was still taking the pills when he lifted the quotes and when he anonymously took to Wikipedia to make his feelings known about his fellow journalists. He gave them up the week his disgrace came to light (along with the antidepressants he was also taking) as he explained to the Guardian in an interview he gave last month to promote his first post-scandal work: a book on drugs called Chasing the Scream.

“I had been swallowing fistfuls of white narcolepsy pills for years… I had read that if you take them you can write in long, manic weeks without pause and without rest and it worked – I was wired,” he writes in the foreword to the book. But he found he had begun to wonder “if I was becoming an addict myself. My long drugged writing binges would stop only when I collapsed with exhaustion and I wouldn’t be able to wake for days.”

Hari’s special subject is drugs. Chasing the Scream is the result of extensive research and has garnered serious critical attention. But he won’t talk about them with me. “It was a terribly painful period of my life and I find it too distressing to discuss in detail in public,” he emails. And he still won’t talk to me when I email back and point out that his article on the joys of Provigil is still all over the internet and is quoted on multiple sites by people who have used it as a reason to try it themselves, so it might be useful for them to know what he thinks of it now. And anyway, I’m interested in the cultural landscape in which these drugs exist, but he won’t be drawn.

He’s made it clear in various interviews that he doesn’t want to blame his behaviour on drugs or to invite sympathy for himself. And correlation is not causation and he, more than anyone, perhaps, is aware of the politics that make any discussion of drugs so fraught and open to misinterpretation. But still. In the absence of proper studies, personal experience, stories, are all that anyone has to go on and he obviously has an interesting one about modafinil that he’s simply not telling.

In the US, surveys have shown the highest levels of usage are at elite universities in the north-east, where academic pressure is at its most acute; where students are most competitive; where intelligence, and all the things that supposedly come from it, jobs, money, success, are perhaps most highly valued, most highly desired.

Sahakian also makes a comparison with cosmetic surgery. “We are already enhancing ourselves in all sorts of ways. I was shocked when those problems with those French breast implants came to light and the number of women who had to have them removed by the NHS. But it just all depends what you’re valuing. And if you go to a good university and expect a high salary, it’s likely you are going to be valuing certain things and if you can enhance these things that’s going to be attractive.”

And in Britain, informal surveys, such as one carried out by student website the Tab, have suggested the highest levels of usage are in the more academic universities – Oxford came top of its poll – and students of subjects with the highest workloads tended to show the highest usage. Rivlin, the editor of the Tab, was studying at Cambridge in 2010 when he first heard about modafinil and started using it. “It was my third year and it suddenly appeared and people were like, ‘It’s amazing. It allows you to concentrate.’ And, you know, there’s a lot of pressure to perform and it was very useful for mechanical academic work when you’re just trying to do a lot of notes or something.

“It probably says a lot about Oxbridge that it seemed to take off there. I remember my friends at other unis hadn’t really heard about it at the time but it’s now certainly bigger everywhere.”

Not that any university I get in touch with wishes to acknowledge this. It’s partly because there is a danger that articles like this, even with all the caveats, might encourage more people to try these drugs. Partly because there’s no good research being done into the numbers of students taking them, though there are all sorts of indices. In October, a record haul of smart drugs being traded over the internet was seized by the UK’s Medicines and Healthcare Products Regulatory Authority.

And Sahakian points to the increasing lifestyle use of cognitive enhancing drugs, or smart drugs, by healthy people. Published figures suggest a large discrepancy between the number of diagnosed narcoleptics and the amount of anti-narcoleptic drugs sold (Cephalon, makers of Provigil, made $1.2bn in worldwide sales in 2012), and the ever increasing amounts of ADHD medications being prescribed (Dexamphetamine is the second most privately prescribed drug in Britain).

But, more than this, it’s a can of worms. Duke University in North Carolina has amended its academic honesty policy to include “unauthorised use of a prescription medication” and Sue Wasiolek, the dean of students, tells me that it was students themselves who lobbied for this. They “wanted it noted for the student community that using drugs to enhance academic performance constitutes cheating”. It’s only gone as far as noting it, though. Without drug testing, it’s hard to see how it could be enforced, though several academics have started calling for that too.

In Britain, the official policy of most universities seems to be to pretend it isn’t happening. When I email Oxford University in search of somebody in student services to talk to about whether they’d encountered any students struggling with these drugs, I get varying sorts of brush-offs before an official statement is issued. But then, it is a tangled, morally difficult subject with no easy answers. Even if you ban it in exams, what’s to stop students using it for revision? And there are cognitive enhancers that have been around for hundreds of years that no one considers “cheating”. Caffeine is one; nicotine another.

But we may all have to consider these ethical questions one day. Because cognitive enhancement isn’t going away. Which is good news for Alzheimer’s and Parkinson’s sufferers. And possibly for the rest of us too. “We live in a global society that is very competitive and where there’s a lot of pressure and stress,” says Sahakian. “And there are lots of difficult questions. If you’re older and your pension is not performing and you have to compete against younger colleagues, what’s the pressure there? If you take one of these drugs, are you enhancing yourself? Or restoring yourself to what you were?”

The Future of Humanity Institute at Oxford University was set up to consider just this sort of question and Anders Sandberg, a computational neuroscientist there, tells me how they look at the biggest threats humanity is facing, as well as opportunities; what emergent technologies may offer us as humans.

And cognitive enhancement, whether it’s a drug, or an electric current across the brain, or a form of brain training on computers, is absolutely part of our future, he says. The difficulty is doing research. “Ethics committees shy away from it. They get nervous. Part of the problem is the word ‘pill’. If you said it was a herb that gave you a better memory, rather than little white pills, people wouldn’t be so scared.”

But, he’s upbeat about their democratising potential. “University is a cognitive enhancement but it’s rather an expensive one. Smart drugs are relatively inexpensive and if they help people increase their opportunities then I think this is a good outcome. The smart people get more competition but a cognitively enhanced society would help us all.”

When I talk to Sandberg, he’s at a conference in Florida, due to deliver the keynote lecture the next day. “So I will take a modafinil after breakfast just to give me that extra edge.” He started taking it about 10 years ago and mostly uses it when “I am trying to solve really hard problems. I think it helps. Though quite often I find I’m not working on the right problem and I would actually probably really benefit from a good time-management course.”

He finds it suppresses divergent thinking, which is one part of intelligence, “but I think I’m too divergent. I never finish stuff. This helps me focus.” Mostly, though, he compares it to a “really good cup of coffee that lasts all day”.

What interests him too is what people say they want to enhance. People take smart drugs to get ahead in their career, or there’s enough of a placebo effect to make them believe that they are. Silicon Valley thrums with it. And Richard Kingdon, who runs a rehab clinic, City Beacon, in London’s Square Mile, tells me that people who come to him with addictions to cocaine and alcohol are often on it too.

“But we could be thinking about enhancements that make our lives happier and more fulfilled,” says Sandberg. “We asked people if they’d take a supplement that enhanced their kindness and empathy and only 9% wanted that.”

It isn’t the drugs. It’s us. We’re medicating ourselves against what used to be considered the problems of everyday life. Sadness, anxiety, overwork. “We really have to look at ourselves as a society,” says Sahakian. “We used to have a childhood. What is causing such stress? And it’s a problem with all types of drugs. If you look at the use of painkillers, it’s enormous. We all believe in the power of the little white pill.”

Danny Lee-Forest, head of operations in the enforcement division of the Medicines and Healthcare Products Regulatory Agency, tells me that smart drugs are just one part of a huge online business. His team seized £11m worth of drugs last year “and it’s mostly stuff that either people don’t want to go to their doctor about or they do, and he tells them something they don’t want to hear, like go on a diet, or do some exercise. It’s slimming pills or erectile dysfunction pills or hair loss.” Or, increasingly, pills to block out the competing distractions of everyday life. Pills to get ahead.

Mike Power, the author of Drugs 2.0: The Online Revolution That’s Changing How the World Gets High, points out that ADHD drugs are amphetamines. “That’s what Adderall and Ritalin are. Those American students are all just speeding off their heads.” And while, it isn’t quite yet that bad here, we are living in a “more narcotised society generally. From the idea of celebrities ‘partying’ or people talking about ‘a big night out’, there is an unacknowledged ubiquity to drugs from the boardroom to the street, but we just don’t have the political or intellectual maturity to discuss it rationally. We just get various moral panics. For better or worse, the internet has opened up access to any number of drugs and we’re just not dealing with it.”

And it’s young people who are caught in the frame. “We have a generation of young people leaving university with mortgage-sized debts and the growth in prescription drugs and appetite for enhancement drugs mirrors that almost exactly.”

In the 60s, tranquillisers were known as mother’s little helpers. Smart drugs are capitalism’s little helpers. Just another symptom of the aching gap in equality that’s opened up: a product of scarcity, of the ever-increasing competition for resources, of a world in which everyone’s looking for an edge.

There’s something that I’ve so far failed to mention. And that is that I researched and wrote most of this article on modafinil. I ordered it from a UK website and received it the next day by Royal Mail special delivery, disguised inside a pouch for “rosehip supplements”. It’s not illegal to buy, only to sell on to others, and I took it in decreasing amounts over three days.

It was only going to be two, but I felt so out of sorts by the third day – dehydrated, headachy, poorly rested, a bit panicked – that I took some to feel halfway normal again. Which is pretty much the definition of dependency. I got a lot of work done. But I would have without modafinil: that’s why deadlines were invented.

And I can’t help thinking about Johann Hari. We’ve all done stupid things, made poor judgments. My suspicion, and it’s only a suspicion since he won’t talk to me about it, is that he doesn’t know what role modafinil played in his own cautionary tale. Did the small white pills have an effect on his behaviour? Did the gorgeous temptress play a role in his downfall? Or was it an accessory after the fact? It’s impossible to know. But I’m not tempted to continue my own experiment.

Young people, students, take it from the expert. Sahakian points out that one of the most effective, best documented and certainly safest cognitive enhancers is entirely free: exercise. Go for a walk, lift some weights, dance. The drugs may work. But they’re not the answer. It’s the world that needs changing, not your brain chemistry.

Some of the students’ details in this piece have been changed

Picture caption interviews by Jasmine Andersson and Shakeel Hashim