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What do the abbreviations written on the prescription my doctor gave me mean?


The Latin and English abbreviations written on prescription are "shorthand" directions for how and when a medication is to be used, and other special directions for use (for example, at bedtime, the number of times a day, orally or topically, and so on) that are put on the container's label prepared at the pharmacy. Reading a written prescription may help you better understand the directions you were given by your doctor. As always though, if you have questions on the directions, check with your doctor or pharmacist.

These are among the most common abbreviations:

  • Sig: write, or let it be labeled (Latin terms: signa or signetur)
  • qd: every day (Latin term: quaque die)
  • bid: twice a day (Latin term: bis in die)
  • tid: three times a day (Latin term: ter in die)
  • qid: four times a day (Latin term: quater in die)
  • qhs: each night (Latin term: quaque hora somni, meaning at bedtime)
  • pc: after meals or not on an empty stomach (Latin term: post cibum)
  • prn: as needed (Latin term: pro re nata, meaning as circumstances may require)
  • po: orally (by mouth) (Latin term: per os)
  • pr: rectally (meaning by suppository) (Latin term: per rectum)
  • sl: sublingually (under the tongue)
  • IM: intramuscularly (by needle, injected into a muscle)
  • IV: intravenously (by a needle in a vein)
  • SQ: subcutaneously (by needle, under the skin)

For example, a written prescription for ibuprofen 600 mg, with these notations: Sig: 1 po qid pc prn is directing the patient to "Take 1 tablet by mouth four times a day after meals as needed."

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Answers to questions regarding information about medications or health conditions are not for diagnostic or treatment purposes and are not conclusive as to the presence or absence of any health condition. Consult your physician for diagnosis and treatment of your medical condition. The information provided is not a substitute for medical advice. Advances in medicine may cause this information to become outdated, invalid or subject to debate. Professional opinions and interpretations of the scientific literature may vary. Walgreens' terms of use and general warranty disclaimer apply to all services provided. If you are in need of immediate medical attention, contact your physician, poison control center or emergency medical professional. If you need to speak with a pharmacist for non-emergency matters, contact your local Walgreens pharmacist or call a pharmacist toll-free at 1 (877) 250-5823.

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