Question of the Day

“prn” or PRN means “as needed.”

Remember “S” for single” (s.i.d.), “B for bi” (twice a day, b.i.d.), “T for tri” (3 times a day, t.i.d.), and “Q for quad” (4 times a day, q.i.d.).

Many clinics use capital letters (SID, BID, TID, QID to mean the same things). q.o.d. means “every OTHER day.” Some clinics instead use “e.o.d.” to mean every other day.

Follow this link to see Table of medical abbreviations.