OP [and anyone else considering being a lab rat], make sure you tell them you have zero allergies, no prior or current health conditions, and are not on any medication.
The smallest things can get you kicked off a study, and you don't want to lose out on free money for being too truthful!
I've never tested actual medication, but I've done dozens of studies involving my skin: sunscreen, soaps, moisturizers, and even "patch tests" where all kinds of items are placed under a square of gauze and stuck to your skin for X amount of hours.
My last patch test had 17 items, including two small pieces of leather, a bit of "fabric" from a dental hygienist's safety mask, various dollops of soap/lotion/moisturizer, and even a few drops of nail polish remover [that last item sucked ass, EVERYONE got a painful rash from it, as expected].
The only unpleasant side effects I've experienced have been some 1st and 2nd degree sunburns from "sunscreen" that didn't freaking work, and one patch study used a different tape on the gauze pads and when it was removed, it ripped off several layers of my skin, leaving my skin oozing blood for a good hour or two.
Oh, I forgot, I also once tested pomegranate [sp?] juice: I had to drink a 350-mL bottle of it once a day for two weeks. It was yummy! [And I'm pretty sure it was for the Pom-wonderful brand of juice, which came on the market shortly after.] I didn't report any side-effects from the juice, because at the time, I didn't know pomegranate juice can affect a woman's menstrual cycle, who'da thunk!
As long as the stuff you're taking is safe, OP, I say go for it. Afaik, there are laws in place that should protect your health while on a study [especially since you're not trying to get treatment for an existing condition].