Understanding What Are the Abbreviations for Pharmacy?

Over 200 reports of medication errors have been linked to misinterpreted abbreviations, highlighting a critical need for clear communication in healthcare. Understanding what are the abbreviations for pharmacy can empower patients and reduce risk. These shorthand notations, often derived from Latin, are still used to convey crucial information about medication orders quickly.

Quick Summary

A comprehensive guide to understanding common pharmacy abbreviations for dosage frequency, route, and timing. Explains their Latin origins, clarifies confusing terms, and outlines current safety recommendations to minimize medication errors.

Key Points

• Latin Roots: Many pharmacy abbreviations are derived from Latin phrases, such as po (per os) for 'by mouth' and b.i.d. (bis in die) for 'twice a day'.

• Frequency Matters: Abbreviations like b.i.d., t.i.d., and q.i.d. are used to indicate how many times a day to take a medication.

• Routes of Administration: Different letters signify the route, such as PO (by mouth), IV (intravenous), or TOP (topical).

• Error-Prone Abbreviations: Certain abbreviations, like q.o.d. and h.s., are known to cause medication errors and are discouraged in modern practice.

• The Push for Clarity: Healthcare organizations, including the ISMP, advocate for spelling out medication instructions to minimize risk and avoid confusion.

• Patients Have a Role: Patients should always ask their pharmacist or doctor to clarify any ambiguous instructions on their prescription label.

The Roots of Pharmacy Shorthand

For centuries, medical and pharmacy professionals have used a system of shorthand to write prescriptions, with many terms derived from Latin. This practice allowed for quick, standardized, and unambiguous communication among clinicians. For instance, the famous "Rx" at the top of a prescription is an abbreviation for the Latin word "recipe," meaning "take thou". While technology has shifted much of this to electronic format, some abbreviations persist, and understanding their origin is key to comprehending their meaning.

Latin and English Abbreviation Examples

Many of the most common abbreviations have simple, direct Latin roots that describe the medication instructions:

• a.c.: ante cibum, meaning before meals.
• p.c.: post cibum, meaning after meals.
• h.s.: hora somni, meaning at bedtime.
• p.r.n.: pro re nata, meaning as needed.
• stat: statim, meaning immediately.
• b.i.d.: bis in die, meaning twice a day.
• t.i.d.: ter in die, meaning three times a day.
• q.i.d.: quater in die, meaning four times a day.
• po: per os, meaning by mouth.
• gtt(s): gutta(e), meaning drop(s).

Decoding Dosage and Frequency Abbreviations

One of the most critical aspects of a prescription is the dosage and frequency. Misinterpreting these instructions can lead to severe consequences. The following are common abbreviations for how often a medication should be taken:

• Daily Dosing:
  • q.d. (quaque die) is used for once a day, but the Institute for Safe Medication Practices (ISMP) recommends writing "daily" instead to avoid confusion with q.i.d..
  • q.o.d. (quaque altera die) means every other day, and should be spelled out to prevent errors.
• Multi-Dose Dosing:
  • q4h: every 4 hours.
  • q6h: every 6 hours.
  • q8h: every 8 hours.
• Timing Specifics:
  • qam: every morning.
  • qpm: every evening.

Routes of Administration and Other Key Terms

These abbreviations specify how the medication should be taken or delivered:

• PO: By mouth.
• IV: Intravenous (into a vein).
• IM: Intramuscular (into a muscle).
• SUBQ or SC: Subcutaneous (under the skin).
• PR: Per rectum (by rectum).
• SL: Sublingual (under the tongue).
• Top: Topical (applied to the skin).
• OD: Right eye.
• OS: Left eye.
• OU: Both eyes.
• AD: Right ear.
• AS: Left ear.
• AU: Both ears.
• c̄: with.
• s̅: without.
• Disp: Dispense.
• Sig: Write (directions on label).

The Risks of Abbreviation and Promoting Clarity

Historically, the use of abbreviations was a time-saving measure, but ambiguous or misinterpreted shorthand has been a source of serious medication errors. Organizations like the ISMP have created lists of error-prone abbreviations that should be avoided. Errors can occur due to illegible handwriting, similar-looking letters, or confusion over multiple meanings for the same abbreviation.

Ambiguous Abbreviation	Possible Misinterpretation	Safe Alternative	Reason for Confusion
q.o.d.	Mistaken for q.d. (daily) or q.i.d. (four times daily)	Spell out “Every other day”	The 'o' can be misread as an 'i' or a period, leading to wrong frequency.
h.s.	Mistaken for HS (half strength)	Spell out “at bedtime”	The capitalization and context can be confused.
d/c	Mistaken for discontinue or discharge	Spell out “discontinue” or “discharge”	Ambiguous meaning, causing potential lapses in treatment.
cc	Mistaken for u (units) or mL	Use mL or spell out “milliliter”	The 'c's can look like 'u's, leading to dosage errors.
U	Mistaken for 0 (zero) or cc	Spell out “unit”	Visual similarity can lead to a tenfold dosing error.
μg	Mistaken for mg	Spell out “microgram”	The Greek letter mu (μ) can be mistaken for an 'm', leading to 1000-fold dosage errors.
MgSO₄	Mistaken for MSO₄ (morphine sulfate)	Spell out “magnesium sulfate”	Similar-looking chemical symbols can lead to catastrophic mix-ups.

The Shift to Electronic Prescribing

The move towards electronic prescribing has significantly improved legibility, but it doesn't completely eliminate the risk of misinterpretation. Healthcare facilities and regulatory bodies now strongly encourage or mandate the use of explicit, spelled-out instructions, avoiding abbreviations wherever possible, especially for high-risk medications. This practice, along with robust pharmacy system checks, helps ensure patient safety.

For a complete list of error-prone abbreviations and recommendations, consult authoritative sources like the Institute for Safe Medication Practices (ISMP) on their website.

Conclusion

While pharmacy abbreviations have a long history and served a purpose, the modern healthcare system is moving toward clearer, more explicit communication to prevent potentially dangerous errors. For patients, understanding common abbreviations is a useful skill for being more informed about their health. However, the most important takeaway is to always ask your pharmacist or doctor to clarify any instructions that are unclear. Don't take chances with your health—when in doubt, spell it out. This shift towards transparent language is a testament to the ongoing commitment to patient safety in pharmacology and medicine.

Frequently Asked Questions

What does 'BID' mean on a prescription?

'BID' stands for the Latin phrase bis in die, which means twice a day.

Why do pharmacists still use Latin abbreviations?

Many of these abbreviations are legacy terms that have become standard shorthand for communicating quickly. However, the use of error-prone abbreviations is being phased out in favor of clearer, spelled-out instructions.

What does 'PRN' stand for?

'PRN' is a Latin term for pro re nata, meaning 'as needed.' It is commonly used for medications like pain relievers or anti-anxiety drugs that are not taken on a fixed schedule.

What is the meaning of 'PO' on a medication label?

'PO' stands for per os, meaning 'by mouth.' It indicates that the medication should be taken orally.

Are there any pharmacy abbreviations that I should be cautious of?

Yes, some abbreviations are considered 'error-prone' due to high risk of misinterpretation. Examples include q.o.d. (every other day) and h.s. (at bedtime), which should be spelled out.

Where can I find more information about dangerous abbreviations?

The Institute for Safe Medication Practices (ISMP) publishes a list of dangerous and error-prone abbreviations and recommends that healthcare providers avoid them. ISMP's List of Error-Prone Abbreviations

What does the abbreviation 'STAT' mean?

'STAT' is from the Latin word statim and means 'immediately.' It indicates that a medication should be administered right away, with no delay.

How can I be sure about my medication instructions?

Always ask your pharmacist or healthcare provider to confirm medication instructions if you find them unclear. It's recommended to have instructions spelled out in full to avoid any risk of misinterpretation.

Why is it important to know pharmacy abbreviations?

Knowing common pharmacy abbreviations helps you understand your prescription instructions and can serve as a double-check on information given by your healthcare provider, promoting your own medication safety.