Can you decipher your medical prescription?

You have just left the surgery with a prescription in your hand. It’s for a new treatment, but hang on a minute, did the doctor say twice or three times a day? You stop and unfold the piece of paper: the name of the drug is clear but after that it’s a muddle of symbols, the only one of which makes sense is the numeral 90. Otherwise you can make out Rx, TID, PO and Mitte and a scrawled signature. None the wiser, you make a mental note to ask the pharmacist about how many times a day you are to take the medication.

An interesting article in the current issue of the New England Journal of Medicine (NEJM) asks the question: "Incorporating indications into medication ordering – time to enter the age of reason?"

Opaque prescription

The authors from Harvard Medical School are concerned that the modern emphasis on patient-centred care notwithstanding, patients are too often left in the dark regarding the purpose of the drugs they have been prescribed. They quote the following argument for opaque prescription writing from 1833, which appeared in the Boston Medical and Surgical Journal, the forerunner of the NEJM.

“The question is often asked, why physicians do not write . . . prescriptions in English. The answer is obvious – that if they did, the patient would often be less benefited than he now is. There are very few minds which have sufficient firmness, during the continuance of disease, to reason calmly on the probable effects of remedies, and to compare their wonted action . . . with the indication to be fulfilled in the particular case. . . . The only state in which the mind can rest . . . during severe illness, is that of implicit reliance in the skill of the physician, and an entire acquiescence in the course adopted, without the slightest question or argument.”

Breathtaking paternalism

Medicine has hopefully moved on from such breathtaking paternalism yet Latin persists in prescription writing. Anecdotally, pharmacists here say that most scripts they dispense contain more English and less Latin these days, but it is rare to see a prescription entirely written in English.

In the US the Joint Commission on Accreditation of Healthcare Organizations (JCAHO) discourages the use of Latin abbreviations as well as other previously accepted abbreviations in the writing of prescriptions.

There is no doubt abbreviations, whether in Latin or English, are a source of healthcare error. For example, a recommended total daily dose of 2,400mg of ibuprofen (an anti-inflammatory drug) should be prescribed as 600mg every six hours rather than 600mg q.i.d. (quarter in die). With the Latin directions, the patient could take all four doses before noon and still feel that he or she was in compliance with the q.i.d. directions.

Most important requirement

The World Health Organisation says there is no global standard for prescription writing. "The most important requirement is that the prescription be clear. It should be legible and indicate precisely what should be given," its prescribing guide says. Here the Medical Council's most recent professional conduct guide states "the prescriptions you issue must be legible, dated, signed and must state your Medical Council registration number".

Meanwhile back with the prescription you were given in the first paragraph, here is a translation of the hieroglyphics. Rx, usually found on the top left of script, comes from the Latin verb recipe and translates as the order "Take". T.I.D is "ter in die" meaning three times a day. P.O. is the Latin abbreviation for " per os" which translates as by mouth or orally. And Mitte followed by a numerical amount translates as "send", meaning "give the patient the following amount".

And here are a few more abbreviations commonly used: a.c is short for ante cebum meaning before meals; alt. die ( alternus diebus) means every second day; and p.r.n stands for pro re nata meaning "as required".

Happy prescription deciphering!

mhouston@irishtimes.com