Think about why you would need a warning label. Oh yeah, because you want to put something into your body that you haven't taken the time to first research and learn about.
Seriously, what the hell.
When the doctor prescribes an antibiotic for my infant son, I remind him that he's also taking Prilosec for reflux and doesn't tolerate milk/soy, and ask if it's still the right thing to prescribe. When I pick up the prescription, I double check this with the pharmacist, and ask him whether I should give the medicines together or at different times, etc. When I get home, I read the labels and papers to see what I need to do for storing the medicine, what the right dosage is, etc.
You want to make this harder... so that "stupid" people will accidentally kill themselves and their children?
I'm good at math and programming. Do I deserve to die because I don't know foobarzacil + bazidrol = heart attack? For anyone who isn't a doctor/pharmacist/expert who has been trained about all of this stuff, having these discussions with experts and reading the labels is doing the research.