You may have trouble swallowing large tablets, or not want to take all the dose of your medicine at one time, but now medical experts have issued a warning after a study found that nearly a third of the split fragments deviated from recommended dosages by 15 per cent or more.

You may think it not important, but there can be serious clinical consequences for tablets that have a narrow margin between therapeutic and toxic doses. There is a particular concern about the practice in nursing homes where many residents are on complex regimes for a range of health conditions, including Parkinson’s, congestive heart failure, thrombosis and arthritis.

Researchers from the Faculty of Pharmaceutical Sciences at Ghent University in Belgium, asked five volunteers to split eight different-sized tablets using three techniques commonly used in nursing homes. It was not good news: 31 per cent of the tablet fragments deviated from their theoretical weight by more than 15 per cent and 14 per cent by more than a staggering 25 per cent. Even the most accurate method produced error margins of 21 per cent and eight per cent respectively.

The end result is tablets are often unequal sizes and a substantial amount of the drug can be lost during splitting. The study involved four volunteers – only one of whom was a nurse in order to replicate common nursing home conditions. Between them they split tablets into 3,600 separate quarters or halves using a splitting device, scissors and a kitchen knife. The eight different tablets were different shapes and sizes, three were unscored, three had one score line and the others had two.

If splitting tablets is something you regularly do, then the best advice is to invest in a splitting device as it gave the most accurate cut. However it still produced a 15 to 25 per cent error margin, but still lower than using a knife or scissors.

The researchers recommended that manufacturers offer more options such as liquid formulations and a wider range of tablet doses. Also that staff in nursing homes should receive training to enable them to split tablets as accurately as possible.