Splitting Pills May Have Risks
Study Shows Patients Who Split Pills May End Up With Doses That Are Too High or Too Low
Jan. 7, 2011 -- Pill splitting, a common practice among many people who are looking to cut medication costs or dosages, is risky business, according to a study in the January issue of the Journal of Advanced Nursing.
Some pills can’t be split 50-50 and there can be a narrow margin between a dose that can help you and one that can hurt you, the researchers report.
“Not all formulations are available for splitting, and even when they are, large dose deviation or weight losses can occur [and] this could have serious clinical consequences for medication with a narrow therapeutic-toxic range,” write researchers who were led by Charlotte Verrue, PharmD, PhD, of Ghent University in Belgium.
In the study, five volunteers split eight different types of pills using a kitchen knife, scissors/hands, or a pill splitter. The participants split the pills into quarters or halves using these three methods. Of the eight types of pills, three had one score down the middle, two had two scores like a cross, and three were unscored. The medications used were for a host of conditions, including Parkinson’s disease, arthritis, and heart disease.
The researchers weighed the tablet and its parts before and after splitting. They found that 31% of the pill slices deviated from their recommended doses by more than 15% and 14% of the pill fragments deviated by more than 25%. Even the most accurate means of pill splitting, the pill splitter, was associated with margins of error.
“We have tested all kinds of tablets: big, small, round, with or without scoring line ... and tried to find an overall method that is best suitable for splitting tablets,” says Verrue in an email to WebMD. “Dose deviation when splitting tablets is not always a problem. For example, for chronic therapies (e.g. hypertension, etc.) it often doesn't matter when a patient takes a little more of a drug one day and a little less the next day. It becomes problematic when we are talking about bigger dose deviations and drugs that have a narrow therapeutic index (i.e. when a small difference in dosage can have a big difference in effect).”
If you must split your pills, use a splitting device, the researchers conclude.