>> why is Tamiflu not sold over-the-counter? <<
Mainly because organized medicine always wants to stifle competition.
But as with antibiotics, there’s also a valid scientfic reason:
Over-the-counter availability could lead to widespread “underdosing” — which in turn might help create strains of resistant flu viruses.
Tamiflu is an amazingly complex compound to manufacture. One of the steps involves azides, the stuff which makes car bags explode.
“which in turn might help create strains of resistant flu viruses.”
That is already happening.
And not only that, but the Tamiflu is showing up in the water supply and rivers, so this will make the resistant flu strains develop even faster because of the exposure of birds to it.