"Prescription confusion" joke

This is a true story which happened to me.
For a while, I worked as a cashier at a local drugstore.
Well, one afternoon, while I was working at the drug counter, a woman came in
and dropped off 3 prescriptions to be filled. Later, she came back, and wanted
to pick up the prescriptions (they were for her husband). Two of the
prescriptions were ready, with the third stapled to the bag. The pharmacist
had already told me about this one.
"Here you go, we were only able to fill two of the prescriptions,"
I said.
"Why can't you fill the other one?" she said.
"I'm sorry, we don't carry that one," I said.
"Well, can you order it?"
"No."
"Well where can I get it filled?"
"I'm afraid you will have to go to the hospital to get it filled."
"Why? What's it for?"
"A chest X-ray."
And some people wonder why patients never know what the h**l is going on!
BTW, the handwriting on the prescription (by the doctor) was one of the
clearest I have ever seen.