[8] A small research project gave a subjective estimate of error rates, including near

misses, from a group of selleck kinase inhibitor pharmacists in South Australia as approximately 1% of all dispensings.[20] Pharmacists registered in Tasmania, Australia, identified similar or confusing drug names as important factors that contribute to dispensing errors in community pharmacies.[23] Pharmacists who had been professionally registered for a longer period of time found such confusion to be significantly less important than pharmacists registered for a shorter time period. Similarly, while improving labels and providing distinctive drug names were considered important factors in reducing dispensing errors a longer period of professional registration was again associated with less importance being placed on this.[23] These findings may be Selleck XL765 related to prescribing frequency being found important in drug name recall.[44] The associations between length of registration and both the importance of the problem, and the importance of improving labels, though significant, were weak.[23] A study of community pharmacies in the UK identified a dispensing error rate of almost 4 per 10 000 items dispensed.[22] Similar drug names were found to be responsible for 16.8% of the errors recorded. Consumers have also identified medication

packaging and labelling, more generally, as major factors contributing to poor compliance and medication safety, particularly in the context of generic substitution.[42] Aronsen has suggested that sources of confusion over medication names can arise from: different medications having similar names; formulations containing different medications sharing the same brand name; the same medicines marketed in different formulations having different brand names; and the use of abbreviated medication names.[26] Brand extension, which is another problem causing confusion, refers to a new product that is a variation (e.g. new formulation

or modified molecule) of an existing product.[24] Brand extensions are an effective way to support price rigidity in products that are going off-patent and can result in products with names similar to existing products. Brand extension leads to problems arising with drug names, particularly Adenosine triphosphate where products with different dosage forms are only indicated by the use of suffixes (e.g. XR, SR and XL in brand names for extended-release products, such as tramadol, tramadol XR, tramadol SR).[29] This has been identified as important for both prescription medicines and over-the-counter (OTC) medicines,[20] though it has been perceived to cause more confusion for prescription than for OTC medications. The rate at which new drugs are introduced onto the market adds to the problem of look-alike, sound-alike medication names.