Going further, the calculations are rule of thumb and generic and each person has to make adjustments based on intuitions about their metabolism, what they ate, what they plan to eat, what activity they anticipate, and when they last dosed. It's every day, for the rest of their life.
[Source]
Scott Hanselman interviews OpenAPS hacker Dana Lewis:
http://www.hanselminutes.com/514/the-open-artificial-pancrea...
It is exceedingly easy to overdose on tylenol, and yet it's available without any controls.
Sex-negative has nothing to do with it. Plan B is non-prescription.
The question is, does something about visiting a doctor to get a prescription for birth control mitigate the risk of a blood clot? Something that there would be no way to replicate with say better women's health education or a nice info-graphic next to the birth control section?
Besides, insulin is available OTC anyway (in the US). It's just that prescriptions make it cheaper/free.