Reading a prescription
Prescription abbreviations,
in plain words.
Doctors often write how often to take a medicine in short Latin abbreviations: OD for once a day, BD for twice, TDS for three times, SOS for when needed, and HS for bedtime. Many prescriptions in India also write the day as numbers, such as 1-0-1. This table gives what each one means and links to a page with its sources.
| Abbreviation | Means | Stands for | Also means |
|---|---|---|---|
| ODo.d., QD (US) | once a day | omni die | right eye (on an eye prescription, from oculus dexter) |
| BDb.d., BID, b.i.d. | twice a day | bis in die | – |
| TDSt.d.s., TID, t.i.d. | three times a day | ter die sumendum | – |
| QDSq.d.s., QID, q.i.d. | four times a day | quater in die | – |
| 1-0-11-1-1, 1-0-0, 0-0-1 | one in the morning, one at night | – | – |
| HSh.s. | at bedtime | hora somni | half-strength (a second meaning that safety groups warn about) |
| QHSq.h.s., qhs | every night at bedtime | quaque hora somni | – |
| SOSs.o.s. | only when needed | si opus sit | – |
| PRNp.r.n. | as needed | pro re nata | – |
| AC and PCa.c., p.c. | before and after meals | ante cibum, post cibum | – |
| BBF | before breakfast | – | – |
These pages explain what an abbreviation means. They don’t say how much to take or when: follow what the doctor wrote, and ask your pharmacist if any part of a prescription is unclear.
Let’s take care, together
Type it as it’s written.
AlongWell sets the reminders.
Add a medicine the way the prescription has it, OD, BD, TDS or 1-0-1, and AlongWell reminds each family member at every dose. Free on iPhone and Android.
