It was the last semester of my undergraduate degree, and I was broke.

I had started college with $40,000 at my disposal, half from a private loan and half from my parents.

The optimistic freshman in me had figured that money, combined with savings from summer jobs and perhaps a scholarship, would get me through.

I was wrong.

University is expensive, and it gets more expensive every year. With living expenses factored in, the average annual cost is now more than $20,000.

Back in 2008, when I was in the fifth year of my four-year degree, it had already hit $17,500.

The bank wouldn't give me more money, and I wasn't eligible for public loans. The Ontario government had determined my middle-class parents earned enough cover for me, when in reality they did not.

My bank account was empty again, and I had two more rent checks to cover before graduation. So after Christmas break, I cut almost everything from my budget except for $1.39 McDonald's cheeseburgers and $1 beers and blanketed my college town with résumés.

I got a job waiting tables at a new Latin restaurant. It seemed perfect. The $20 an hour I was making with tips was enough to pay my February rent. But the restaurant shut down a few weeks after I started. I guess my little white college town wasn't ready for mole.

I couldn't find another serving job, and I was starting to get desperate. I was starting to think I would need to go back to the Subway where I worked the previous summer.

I typed up a cover letter detailing my many years of sandwich artist experience, but I didn't send it.

Returning to Subway was my nightmare. The pay there was just over minimum wage, plus one foot-long sub per shift, and that never felt like enough to deal with long lines of wasted freshmen who couldn't decide between steak and chicken at 3 am.

Leafing through the classified section of a free paper looking for a job that would save me from Subway, something caught my eye:

HEALTHY MALES AND FEMALES NEEDED FOR INVESTIGATIONAL STUDY INTO GRASS ALLERGY MEDICATION. COMPENSATION: $900

It seemed like a sign. Not only did I have a self-diagnosed grass allergy, but the $900 promised was exactly what I needed to cover my remaining two $450 rent payments. I figured my credit card could cover the rest.

The study would last a few hours each Saturday for five or six weeks. I'd endure grass pollen and pop an experimental allergy pill.

I bused to the lab and rolled up my sleeve.

"Sorry," said the allergist, minutes after he'd pricked me. He seemed genuinely apologetic when explaining I was actually allergic to oaks, not grass. I would not be earning $900.

But the receptionist did hand me $50 cash on my way out, and it was the easiest $50 I had ever made.

As soon as I got home, I began Googling for more paid studies.

When I began looking for other lab rat opportunities, I learned that Toronto has private medical research facilities all over the place. The city's ethnic diversity — more than 40 percent are black, Chinese, Filipino South Asian, or Latin American — makes it appealing to companies testing out drugs. There's Apotex in the north end, which advertises that it can house 100 subjects at a time. There's Pharma Medica Research in the east end with its "360-bed facility." There's also INC Research downtown, which advertises an "84-bed unit" and "a database of 30,000 subjects."

There were plenty of studies to choose from, but one stood out. It was seeking healthy men and women ages 18 to 55 for seven three-night weekend stays in the clinic. Compensation: $5,930.

That was more than enough to cover my rent. It was also enough to buy my ticket to Vancouver, where I was accepted into a graduate program in journalism starting in September. It was even enough to pay for a ticket to see Radiohead in Montreal later that summer, which was my other big priority at the time.

Like a scene from a prison movie, the door shut with a thunderous thud. I realized was actually locked in. Within days, I was in an office downtown answering questions for a nurse with a checklist. She asked me every imaginable detail of my medical history and took blood to test for HIV and illegal drugs.

She then gave me a packet of information explaining how it would all go if I were accepted.

There would be a three-night trial period where I would stay in the clinic but not take any medication. If I didn't freak out, I would be back for six more weekend stays.

The package explained that the point of the study was to test the "addiction potential" of an experimental "anti-obesity" medication. I found that fortuitous considering I had been subsisting mostly on McDonald's cheeseburgers and $1 beers for several weeks.

It also explained that the drug had already been tested for safety on animals and a few dozen Europeans. I found that reassuring, since it suggested I was unlikely to drop dead.

If I made it past the trial period, I would get placebos in two of the six weeks, amphetamines in two other weeks (a big dose and a small dose), and the mystery "study drug" in the other two (again, a big dose and a small one). The test would be double blind. In other words, I'd have no way of knowing which ingredient was in the pills ahead of time, and neither would the handlers.

Days later, I was back in the clinic for the trial period.

A hulking guard explained the rules: No street clothes, food, cigarettes, or electronic devices were allowed inside. He didn't explain why.

He handed me blue scrubs, a black garbage bag, and a cup to pee in for the weekly drug test. I could keep my course books and highlighters, but everything else went in the garbage bag, which he then put in a locker.

I changed into the scrubs, and the guard snapped a hospital-style band on my wrist with a number.

I was buzzed into the lab.

Like a scene from a prison movie, the door shut with a thunderous thud. I realized was actually locked in.

The prison movie similarities didn't end there. Inside were dozens of rough-looking people with bad tattoos and greasy hair, all in the same blue suits. Almost everyone was shifting around impatiently in front of a single old TV. I wondered how some of them had passed their drug tests.

I knew it would be boring, but with my final research papers due four weeks later, I had plenty of reading to get out of the way. I was relieved to find an empty desk at the end of a long hallway. It had a window view of the expressway, which was a comforting connection to the outside world.

I got out my highlighter and began to read. The hours ticked by painfully.

Dinner afforded a break from the monotony, but it wasn't exactly relaxing. It had to be eaten with guards watching over. Once they saw it was all consumed, they'd checked the number on the wristband and put a check mark on their sheet.

After three fitful nights on thin white cots, interspersed with studying, meals, and boredom, I was free to go.

The following Friday, I was back for the real thing. The routine on the first two nights was the same: study, meal, study, meal, sleep.

Sunday was the big event. Our handlers awoke us around 7 am and sat us in two rows of plush gray lab chairs with our numbers on sheets of printer paper taped to the headrests.

We didn't have names: We were Study Participant 1, Study Participant 2, Study Participant 3, etc.

I was Study Participant 10, which annoyed me, because it meant I got to leave 10 minutes later than Study Participant 1.

One by one, at our allotted times (7:01 for Study Participant 1, 7:02 for Study Participant 2, etc.), we were handed a paper cup of water and another cup of blue capsules. The pills were always the same number, shape, and color. After we threw them back, a hand in a baby blue latex glove would stick a tongue depressor in our mouths, and another hand would shine a flashlight beam into the back of our throats to make sure we swallowed.

An hour later came the fun part. Just after 8 am (8:10 in my case) the handlers rolled up computers in front of our chairs.

The task was to use joysticks to fly little planes around obstacles on the screen with increasing speed, presumably to test coordination. I'm not much into video games, but it was a huge relief from the boredom.

Then came the true or false quiz, completed on another computer. It was the same 50 or so questions every time, all about how we were feeling.

Only one question that still stands out: "I feel in perfect harmony with the world right now. True or false?"

The first week of the study, this was definitely false. I felt more groggy than anything. It must have been a placebo.

It seemed obvious some of my fellow guinea pigs had gotten the real thing. They were wide awake and chatting up the nurses, who would draw blood once an hour after the video games and quizzes.

The routine — video game, quiz, nurse taking blood — took about 15 minutes. That gave me plenty more time to read and highlight. The whole thing was repeated every hour until just after noon, when we were finally allowed to leave the chairs.

Monday morning was a repeat of Sunday morning, but without any drugs. After four hours of joysticks, quizzes, and needles, we were handed a boxed lunch and an orange juice and were buzzed out of the lab.

The second week was more interesting. After popping my pills on Sunday, I came to understand why the true and false quiz was asking me if I felt in "perfect harmony with the world." It really was an ideal description for the warmth and clarity the drug engendered. I remember thinking that if the purpose of the study was to prove this medication wasn't addictive, it might have failed. Then again, I might have gotten the amphetamine that week.

The good news was that there was no apparent damage to my heart In addition to the "perfect harmony," the drug made my rural Ontario history course seem a lot more interesting. One article on proto-feminists from Victorian-era Ontario seemed like divine revelation. The hours zoomed by as I vigorously highlighted journal articles and made notes in the margins, in between the computer tasks and the bloodwork.

One week, a Jamaican guy who was tired of the portable DVD player he had managed to get past security struck up a conversation. I told him I was in university, and he told me he had kids about my age in college. He told me he'd moved to Canada for a better life and, apart from the weather, had been happy.

But he was worried about turning 55. That was the standard age cutoff for medical studies, he explained. Without medical studies paying him upward of $1,000 a week, he was facing a return to the $10-an-hour fast-food jobs he'd done before he became a professional lab rat.

I told him I could relate.

Four weeks into the study, I got a dose of something that wasn't a placebo. A big dose. My heart raced all morning, and the nurse stuck pads on my chest to monitor my heart with telemetry. While everyone else went back to watching TV, I was forced to lie in a bed while the handlers called in a doctor. I didn't think I was going to die, but I was worried that I had damaged my heart.

By the time the doctor arrived, my heart had calmed down. Still, I felt like I'd climbed a mountain. He told me I was safe to go home but would have to report to a cardiac clinic the next day for some tests.

The waiting room at that dingy clinic was full of pallid older people whose heart failure was written on their clammy skin. When my number was called, the workers injected me with radioactive dye, made me run on a treadmill, and took an MRI of my beating heart.

A couple of days later, the doctor phoned with what he called "the good news and the bad news."

The good news was that there was no apparent damage to my heart. The bad news was that my reaction to the drug meant I wouldn't be allowed to finish the study and collect the full six grand.

He also regretted to inform me that I wouldn't be allowed to participate in future medical studies.

That was fine. I didn't really need more money. I was almost done with my university degree and about to start a master's.

I was in debt, sure, but confident I would get a white-collar job and pay all it back.

I returned to Toronto a few days later and picked up a check for around $4,500. I paid my rent, booked my flight to Vancouver, and bought my ticket to Radiohead.

Once in a while, I think about that Jamaican guy and feel a little guilty. He must be over 60 by now.

I wonder if he's working in fast food, serving drunk students at 3 am.

Josh Dehaas is a Toronto-based writer and editor who mostly covers politics for CTVNews.ca. You can find him on Twitter.

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