They're pretty common. I had a sinus infection earlier this year that wouldn't go away and had to get some antibiotics. I picked up the RX from a local Walmart pharmacy (closer to where I live) and they use the same double-sided caps.
But again, it's like the other OP said: The childproof side is the one that they put on first which could present an issue for older people. I'd imagine you could ask them not to do that, though. I never really thought about it.
