For years, I've carried a week's supply in one of those silly long-rectangle 7-box containers with day of the week marked on each little box. Rubber banded to keep it from popping open. For subsequent days the rest is dumped in a big zip-lock bag. Never been questioned yet. Trips from US to Europe, Mid-East and Eastern countries.

I've read I'm supposed to carry prescriptions, but haven't done so.