(CNN) Indianapolis resident John Oriez got a tiny tattoo on his head for the sake of science.
"This was about 15, 20 years ago back when I was losing my hair and was somewhat vain and cared about it," the now-bald Oriez said. "Obviously, it didn't work, but it was interesting."
Oriez is one of thousands of Americans who volunteer their body and time to be a part of a scientific experiment. He's volunteered for a few over the years. "I'm always interested in helping others if I can, and a lot of this is self-interest, as well," Oriez said. "If I'm one of the first to get access to a drug, that could work that is a real benefit."
People who volunteer for these trials can be anyone from a healthy student who needs to make a little extra cash to a desperate cancer patient hoping an experimental drug really can help.
Ads asking for volunteers are ubiquitous, on the backs of buses and on Craigslist. But who really volunteers to become a proverbial human guinea pig? And exactly how safe are these trials?
This system was called into question last month when a clinical trial of a pain medication in France went horribly wrong. While the health ministry is still investigating what happened, five people were hospitalized and one volunteer died. All these volunteers started the study healthy and now some may leave with a permanent disability.
The case made international headlines, but the experts said it's highly unusual. The Food and Drug Administration monitors all U.S. drug trials. Adverse events like what happened in the French case are "extremely rare." The FDA put several fail-safes in place to ensure even the early stage of a trial is safe.
"Under U.S. FDA regulations, sponsors may not start clinical studies for 30 days after the sponsor submits a new Investigational New Drug (IND) application, and this delay is intended to provide the FDA with time to review the proposed study and determine if it is reasonably safe to proceed," FDA spokesperson Tara Goodin said in an email.
"If at any time the FDA determines that human subjects are or would be exposed to an unreasonable and significant risk of illness or injury, the FDA may place the study on 'clinical hold,' which prohibits further investigation until the FDA's safety concerns are adequately addressed and the FDA removes the clinical hold order," Goodin said.
That's good news for people like volunteer Steve Reszka. The Buffalo, New York, resident has diabetes and high blood pressure and saw an ad asking for diabetes drug trial volunteers a couple of years ago. He signed up, hoping to help the greater good.
"My mom's brother was a full-blown diabetic and he died far too early. My mom's sister also died after having diabetes," Reszka said. "I signed up for a trial in part to be altruistic and in part because I wanted to see if the drug they were testing would help me."
To be a volunteer, he sat for a couple of hours of preliminary tests. He'd check in for weekly injections. Reszka kept journals and did blood tests at different intervals. There was a "ton" of safety paperwork to fill out, too. Despite the warning language in the paperwork, Reszka said he felt perfectly safe especially since this wasn't an early stage trial like the French one was. "I felt confidence I wasn't going to be in a position where I would grow a second head or anything," he said.
The trial lasted about six months. Much to his disappointment, the drug -- it could have been a placebo -- didn't have an impact on Reszka's diabetes nor did it help his weight, which was one of the side effects a nurse explained to him. "The weight part was a particular disappointment," Reszka joked.
The tests themselves are designed to keep a volunteer informed about the risks. Instructions are supposed to be written at a sixth-grade reading level. A trained professional walks the volunteer through instructions page by page and a volunteer signs off on each one. Then the volunteer is left alone in the room with the papers so that he or she don't feel pressure to sign them, said Dr. David Gortler.
Gortler, who worked with the FDA in the past and is now a consultant, agrees that the French case was an exception. "I've worked in drug development for 20 years and seen some crazy wacky things, but nothing was as upsetting as that," Gortler said. "That was very unusual. Usually you'd see signs in the animal testing that there could be a problem and these are extensive, exhaustive tests."
Gortler said it's always been easy to recruit volunteers. Some people sign up for the small stipend many trials offer, others say they want to help others. Gortler is grateful for the volunteers, but he said he personally wouldn't volunteer, particularly in an early-stage trial. "But I'm a research scientist. I've seen everything that is bad and had enough concerns over the years that I personally wouldn't take the risk," he said. As far as later phases of the trials, he wouldn't be as concerned.
Other clinical researchers wouldn't hesitate to encourage people to volunteer.
"Clinical trial participation should be considered by everyone since they represent a highly important form of research whose results can improve health and disease outcomes on a global basis," Dr. Wendy Parulekar, president of the Society for Clinical Trials and a cancer researcher, said in an email. "By participating in a clinical trial, an individual can make a contribution to science, medicine and daily living that can be truly impactful and affect generations to come."
The key, she said, is to be an "active participant -- informed and engaged."
If you are considering volunteering she suggests asking several questions: Why is the study being done? Who has approved the protocol? How will the progress of the study be monitored? If I do not participate in the study, what care will I receive?
How many other people will participate? What does participation mean? What tests or treatments will be administered and how long will I be followed? What are risks of participation? What if I withdraw from the study -- how does that impact my care? When will the results of the study be known and how will they be communicated to me?
What additional resources are available for me to help me make my decision? Is the trial registered and information available on an official website? Are there additional costs to me and what compensation is available if there is a mishap/injury? How will confidentiality regarding my data and participation in the study be maintained? What is the relationship of the individuals conducting the research and the intervention being tested?
If you don't like the answers to any of these questions, you can choose not to volunteer. The NIH has a nice FAQ about clinical studies if you'd like to know more. The Clinical Center Patients' Bill of Rights which protects you when you volunteer also explains your rights. They have a phone number you can call if you do have questions about your rights.
While the drug trial Steve Reszka was a part of didn't work out, he said he still left the experience feeling good about what he did and he'd volunteer again.
"Maybe down the road this volunteering could help," Reszka said. "Even if this is a small part to play, helping science like this, even a little, it's definitely a good thing."