So yesterday I asked Mrs. Brainless if she needed any refills on her seizure medication, and she said no.
Last night, around 9:00, a pharmacist called me. Mrs. Brainless was there, needing a refill on her med. The same one I'd offered to refill earlier (for the record, she told the pharmacist it was "my seizure pill, whatever it's called". Fortunately, they know her there and could look it up).
I authorized the refill, then called her cell phone (1-800-BRAINLESS), and asked her why she'd told me she didn't need any refills a few hours earlier.
"I didn't then. I still had one pill left for my night dose. But I took it, and now I'm all out, so I'll need some for tomorrow morning".