Correspondence
The Naming of Drugs Is a Difficult Matter
N Engl J Med 1994; 331:1163October 27, 1994
- Article
To the Editor:
I would like to report on two medications with similar names and dosages, which may be a source of errors by pharmacists. A 54-year-old woman with hypothyroidism due to total thyroidectomy for thyroid carcinoma had been prescribed levothyroxine (brand name, Levoxine) at a dose of 0.125 mg daily. However, her thyroid-function tests revealed very low concentrations of free thyroxine (0.33 ng per deciliter; normal range, 0.71 to 1.85) and triiodothyronine (0.4 ng per milliliter; normal range, 0.6 to 1.8) and a very high concentration of thyrotropin (162.39 microU per milliliter; normal range, 0.35 to 5.5). When the patient's medications were reviewed, it was discovered that she was receiving digoxin (brand name, Lanoxin), also at a dose of 0.125 mg per day, instead of Levoxine.
When handwritten, these two brand names are very similar; the e and v in Levoxine can easily be misread as the a and n in Lanoxin. Furthermore, because these two drugs have the same dosage (0.125 mg per day), the likelihood of error increases. For each of these medications, different brands have different absorption rates, and they are often prescribed by their brand names.
Paying attention to this similarity can prevent further errors with grave consequences.
Ghassem Pourmotabbed, M.D.
University of Tennessee College of Medicine, Memphis, TN 38163- Citing Articles (2)
