Health Education

Decode Your Prescription: What strict 1-0-1 & OD Mean

Pharmacist John Doe
Feb 05, 2025
6 min read
Decode Your Prescription: What strict 1-0-1 & OD Mean

The Secret Language of Pharmacists

Doctors often use Latin abbreviations or shorthand numbers to indicate dosage frequencies. Misunderstanding these can lead to under-dosing or dangerous overdosing.

Common Number Patterns

Code Meaning
1-0-1 Take 1 in the morning, 0 at noon, 1 at night (Twice a day).
1-1-1 Take 1 in the morning, 1 afternoon, 1 night (Three times a day).
0-0-1 Take 1 only at night (common for sleep meds).

Latin Abbreviations

  • OD (Omne Die): Once a day.
  • BD / BID (Bis in Die): Twice a day.
  • TDS / TID (Ter Die Sumendum): Three times a day.
  • SOS (Si Opus Sit): If needed (e.g., for pain or fever).
  • AC (Ante Cibum): Before food.
  • PC (Post Cibum): After food.