A pharmacy received the following prescription:Ibuprofen 800 mgSig: i tab PO t.

The original sig reads:

“i tab PO t.i.d.” which means “take one tablet by mouth three times a day”.

If the label instructs twice daily (b.i.d.) instead of t.i.d., it is a dosage frequency error, leading to under-dosing.

According to Mosby’s Pharmacy Technician: Principles and Practice:

“A transcription error in the frequency of administration can result in subtherapeutic dosing or treatment failure. Accuracy in translating sig codes is essential.”

Other options:

Route (PO) is correct.

Days supply is still 7 days.

Dosage form (tablet) is unchanged.