Prescription errors are one of the main causes of malpractice claims against physicians. Preventable errors include prescribing the wrong drug or dose, prescribing drugs to which patients are allergic, and prescribing drugs that have adverse interactions with other drugs patients are taking. Studies show that medication mistakes, in and out of the hospital, account for an estimated 7,000 deaths a year in the United States. A five-year study by the Food and Drug Administration published in 1998 tracked 6,000 reports of medication errors that caused 332 deaths, 235 life-threatening events and 1,273 severe injuries.

Safeguarding against error
Improving patient safety and reducing the threat of claims require implementing straightforward, standardized procedures that diminish the potential for error. The National Coordinating Council for Medication Error Reporting and Prevention and the American Hospital Association are spearheading efforts to help achieve safer medication administration systems. The following guidelines are based on recommendations they compiled with the help of several expert sources.

Write clearly.
About 15% of prescription errors result from bad handwriting. Use block printing to improve legibility.

Include a brief notation of purpose on prescription orders (e.g., for cough) unless deemed inappropriate.
Notation of purpose creates an extra safety check in the medication prescribing and dispensing process. Certain diseases and medications, however, may warrant confidentiality.

Include age and, when appropriate, weight of the patient on the prescription or medication order.
The most common errors in dosage occur in pediatric and geriatric populations, in which low body weight is common. Noting the age and weight of a patient allows the dispensing healthcare professional to double-check the drug and dose.

Use the metric system.
The metric system is used in drug product labeling and package inserts. Likewise, use the metric system for all prescription orders, except for therapies that use standard units (such as insulin and vitamins). Abandoning the archaic apothecary and avoirdupois systems will help avoid misinterpretations of abbreviations and symbols, and miscalculations when converting to metric.

Always specify concentration.
Use mcg, mg, or g for prescription strength rather than writing, for example, “Tylenol, 2 tabs.”

Use full generic names of drugs.
This will help avoid confusion between look-alike drug names. Incorporate computerized alerts for look-alike and sound-alike drug names and keep translation charts of brand and generic names at hand.

Here are just three examples of the many medications causing serious mix-ups:

• Hespan, a plasma expander sometimes used in patients who are actively bleeding, and Heparin, an anticoagulant.
• The painkiller Celebrex and the antiseizure drug Cerebyx.
• Xeloda, an oral antineoplastic agent, and Xenical, an antiobesity agent.

Don’t abbreviate directions for use.
These abbreviations are particularly dangerous because they have been consistently misunderstood:

• U (units) is commonly mistaken as a zero or a four (4), resulting in overdose. It’s also mistaken for cc (cubic centimeters) when poorly written.
• ug (micrograms) is often mistaken for mg (milligrams), resulting in overdose.
• Q.D. (daily) is often mistaken for Q.I.D. (four times daily) because the period after the Q has been misread as an I.
• SC or SQ (subcutaneous) can be mistaken for SL (sublingual) when poorly written.
• TIW (three times weekly) can be misinterpreted as three times a day or twice a week.
• HS (half strength) is sometimes misinterpreted as HS (hour of sleep).
• cc (cubic centimeters) can be mistaken as U (units) when written poorly.
• AU, AS, AD (both ears, left ear, right ear respectively) can be misinterpreted as OU, OS, OD (both eyes, left eye, right eye).

Put a zero in front of a decimal expression of less than one.
A leading zero should always precede a decimal expression of less than one. On the other hand, a terminal or trailing zero should never be used after a decimal. Tenfold errors in drug strength and dosage have occurred with decimals due to the use of a trailing zero or the absence of a leading zero.

Give patients specific instructions.
Prescribers should not give vague instructions such as “Take as directed” or “Take/use as needed” as the sole direction for use. Specific directions to the patient help reinforce proper medication use. Explain medications and their side effects and have patients repeat instructions. Tell patients which side effects should prompt concern. Clear directions also enable the dispenser to check the proper dose for the patient.

Take inventory.
Tell patients to “brown bag” their medications. Have them throw everything in a bag—including over-the-counter drugs and drugs prescribed by other physicians—and bring the bag in. Weed out duplicates of brand and generic drugs and designate a place for a detailed medication history in your charts.

Conclusion
Minimizing prescription errors requires standardizing prescribing and communication procedures and implementing a simple system of safety checks. It also requires educating patients about their medications: what they look like, why they were prescribed, the proper doses and the possible side effects. By working together as a team and paying careful attention to the medication administration process at every step, the prescriber and patient can help ensure a safer and more appropriate treatment plan.