Abbreviations (most are from Latin) are often used by prescribers. The pharmacist then translates into plain English on the pill bottle. Some physicians are moving away from the following abbreviations and write out the prescription in plain English.
General Abbreviations
Pt. means “patient” and Rx means “script” or prescription, as in “Pt needs Rx for penicillin.” Or one could say, “Pt. needs script for penicillin.” More recently, one might see the abbreviation ERx, for “electronic prescription.”
Route of Administration
Medications can be delivered by mouth (p.o. means per os or “by mouth”), intravenously (IV), intra-muscularly (IM) or subcutaneously (subQ or SQ). Of course, virtually every outpatient Rx will be p.o. Hospitalized patients are more likely to receive IM, IV, or SQ.
Prescription Quantity and Refills
An Rx must specify the number of pills or quantity of liquid that comprises the prescription, and number of refills, if any. Usually, one sees only “#40” or similar for pills or capsules. Or one could see ml (millileters), or oz (ounces) for liquid medications.
Dose/Quantity
Medications are quantified generally in milligrams (mg). Exceptions occur, such as for Botox (units) and synthroid (micrograms, or mcg). And with liquid medication, rather than refer to mg, etc., the clinician might write gtts (drops), or the more familiar tsp (teaspoon), tbsp (tablespoon), oz (ounces).
Frequency of Administration and other Directions
This follows the “sig,” which stands for signetur, meaning “let it be labeled,” which is another way of saying “directions.” The “Q” or “q” is Latin for quague which means “once.” “B,” “T,” and “Q” stand for bis, ter, and quater which mean 2x, 3x, and 4x, respectively.
- PRN – pro re nata, meaning “as necessary.”
- QD – “every day,” or “once a day.”
- QOD – “every other day.”
- HS – (hora somni) means “at bedtime.”
- BID – twice a day or every 12 hours
- TID – three times a day or every 8 hours
- QID – four times a day, or every 6 hours but, most people take 4x a day while awake, which means first thing in the morning and at bedtime for the first and last dose of the day.