It is a standing joke that physicians have horrible handwriting. It turns out this may not be such a laughing matter. A number of studies have found that sloppy handwriting is just as deadly to patients as the disease for which they sought treatment.

The quality of physician handwriting is a widespread problem. A 2002 report in the Journal of the Royal Society of Medicine revealed that 15% of medical case histories were illegible. As troubling as that can be, a case history is primarily used by the treating physician, who, presumably, can read his or her own handwriting. When other professionals have to rely on doctors’ penmanship, the results can be disastrous.

One problem is that many medications have similar names but dramatically different uses. Poor penmanship on prescriptions has frequently caused confusion between medications such as the pain reliever Celebrex and the antidepressant Celexa, or the tranquilizer Zyprexa and the antihistamine Zyrtec.

University of Minnesota researchers looked at 12 studies that compared medication errors with handwritten and computerized prescriptions from in-hospital doctors. Nearly a quarter of all hospital patients experience medication errors, a rate that increased from 5 percent in 1992, according to the study.

Sloppy handwriting in school can result in lowered grades. The consequences in the medical field are much more serious. Consider a case out of Texas in 2013, where the doctor’s handwriting was so illegible that a patient was given 120 millamoles of potassium, instead of the 20 mills modes the doctor intended. The mistake cost the patient his life.

A ScienceDaily report concluded that illegible handwriting and transcription errors are responsible for as much as 61 percent of medication errors in hospitals. The National Academies of Science’s Institute of Medicine determined in 2006 that these types of mistakes harm as many as 1.5 million Americans each year and result in more than 7,000 unnecessary deaths.

The next time you receive a prescription from your physician and the handwriting seems a bit unclear to you, it is probably a good idea to assume it might be just as illegible to your pharmacist. Do yourself a favor and follow the example of your elementary school teacher: return the paper and ask that it be rewritten.

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