Here are some common abbreviations, used by a doctor to indicate the timing of a medicine to be taken. These are Latin words and their full forms are as follows:
AC / Ante cibum – it means “Before meals”, i.e. to be taken before meals.
PC / Post cibum - it means “After meals”, i.e. to be taken after meals.
QDS / QID / Quater in die - it means “Four times a day”, i.e. to be taken four times a day.
TDS / TID / Ter in die - it means “Three times a day”, i.e. to be taken three times a day.
BD / BID / Bis in die - It means “Twice a day”, i.e. to be taken two times a day.
OD / Omnie die - It means “Once a day”, i.e. to be taken once in a day.
PRN / Pro re nata - It means “As needed”, i.e. to be taken as needed.
QD / Quaque die - It means “Every day”, i.e. to be taken as every day.
QOD / Quaque altera die - It means “Every other day”, i.e. to be taken every other day.
HS / Hora somni - It means “At bedtime”, i.e. to be taken at bedtime.
STAT / statim - It means “Immediately”, i.e. to be taken immediately.
Doctors use these abbreviations to specify the frequency and timing of medication doses in their prescriptions. However, it's essential for patients to understand these abbreviations clearly and, if uncertain, ask their healthcare provider for clarification. Using the wrong timing or dosage can impact the effectiveness and safety of the medication.