Definition of Drug, prescription
Drug, prescription: A drug requiring a prescription, as opposed to an over-the-counter drug, which can be purchased without one. The word "prescription" comes from the Latin "praescriptus" compounded from "prae", before + scribere, to write = to write before. Historically, a prescription was written before the drug was prepared and administered.
A prescription has several parts. There are:
Seen on a prescription, b.i.d. means twice (two times) a day. It is an abbreviation for "bis in die" which in Latin means, not too surprisingly, twice a day. The abbreviation b.i.d. is sometimes written without a period either in lower-case letters as "bid" or in capital letters as "BID". However it is written, it is one of a number of hallowed abbreviations of Latin terms that have been traditionally used in prescriptions to specify the frequency with which medicines should be taken. Other examples include:
Last Editorial Review: 7/1/2016
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