Prescriptions are fundamental to modern healthcare, serving as a written order from a healthcare provider for a specific medication. These documents contain several key pieces of information, including the patient’s name, the drug name, its strength, and the quantity to be dispensed. Among these details, the “Sig” section provides instructions for patients on how to use their prescribed medicine. This section helps ensure patients understand their treatment regimen.
Decoding the “Sig”
The term “Sig” on a prescription is an abbreviation derived from the Latin word Signatura or signetur, meaning “to label” or “let it be labeled.” Its purpose is to convey explicit instructions on how to take medication, interpreted by the pharmacist from the prescriber. This section details the dosage, frequency, route of administration, and any special considerations for the drug’s use. Pharmacists translate the abbreviated “Sig” information provided by the doctor into clear, understandable language on the medication label you receive. This translation ensures you have the information needed to follow your treatment plan.
Common Sig Abbreviations and Their Meanings
The “Sig” section frequently uses a standardized shorthand system, primarily rooted in Latin abbreviations, to concisely convey instructions. Understanding these common abbreviations is important for patients, even though pharmacists typically translate them into plain English on the prescription label.
Frequency Abbreviations
- Bid (bis in die): Twice a day
- Tid (ter in die): Three times a day
- Qid (quater in die): Four times a day
- Qd (quaque die): Every day
- Qod (quaque altera die): Every other day
- Hs (hora somni): At bedtime
Route of Administration Abbreviations
- PO (per os): By mouth
- PR (per rectum): Rectally
- SL (sub lingua): Under the tongue
- Top: Topical application
- AAA: Apply to affected area
Other Common Abbreviations
- AC (ante cibum): Before meals
- PC (post cibum): After meals
- Prn (pro re nata): As needed
- Stat (statim): Immediately
- Gtt: Drop or drops
- Tab: Tablet
Why the “Sig” Matters for Your Health
Understanding and adhering to “Sig” instructions is important for medication effectiveness and patient safety. Taking medication incorrectly, such as at the wrong dosage or frequency, can lead to treatment failure or severe health complications. For example, under-dosing might result in the medication not working as intended, allowing a condition to worsen, while over-dosing can cause adverse side effects or toxicity. The CDC reports that not taking prescribed medications as instructed contributes to chronic disease treatment failures and preventable deaths annually. Therefore, if any part of your medication instructions is unclear, it is important to ask your pharmacist or doctor for clarification.