Health and Medicine

Drugs and Medicines

What is the meaning of the abbreviations often used by a doctor when writing a prescription?

Latin Phrase Shortened Form Meaning
quaque hora qh every hour
quaque die qd every day
bis in die bid twice a day
ter in die tid three times a day
quarter in die qid four times a day
pro re nata prn as needed
ante cibum a.c. before meals
post cibum p.c. after meals
per os p.o. by mouth
nihil per os n.p.o. nothing by mouth
signetur sig let it be labeled
statim stat immediately
ad libitum ad lib at pleasure
hora somni h.s. at bedtime
cum c with
sine s without
guttae gtt drops
semis ss a half
et et and


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