Revised: 3 May 2013
INN (international non-proprietary names) is a nomenclature system used to identify active ingredients of medicines. Each INN is a unique name that is internationally consistent and globally recognised.
The INN system began operating in 1953 and is now administered by the World Health Organisation. The aim of the INN system is to provide healthcare professionals with a unique and universally available designated name to identify each pharmaceutical substance. The existence of such a nomenclature assists in the clear identification, safe prescription and dispensing of medicines to patients; and facilitates communication and exchange of information among healthcare professionals and scientists world-wide.1
New Zealand legislation requires medicine labels to include certain information, including specifying the active ingredients. The medicines legislation does not specify which nomenclature system is to be used to identify the active ingredients.
There is a range of nomenclature systems in existence world-wide for active ingredients, including the BAN (British Approved Names), USAN (United States Adopted Names), AAN (Australian Approved Names) and INN. Medsafe has always accepted medicines and labelling that uses any of these nomenclature systems.
New Zealand is a small market and due to economy of scale, the medicines supplied here are often batches of product produced or packaged for a larger or international market. If that other market is in a country that requires medicines to be labelled as INNs, then NZ is likely to receive INN-labelled medicines.
Globally, medicine manufacturers are rationalising production and this can limit the range of products available for supply to New Zealand. Increasingly, countries with large markets (due to their population size), and thus a critical mass, have required medicine manufacturers to adopt the INN when labelling their medicines. As a result, New Zealand is receiving an increasing number of medicines labelled with INNs. However, the use of INNs is not new in New Zealand. Thyroxine has been labelled as levothyroxine since January 1998; and since May 1999, there has been an amoxycillin product labelled by the sponsor as amoxicillin.
Healthcare professionals have a professional and ethical responsibility to accurately identify the medicine prescribed, whether it be a new active ingredient, a change of brand name, or a different spelling or nomenclature for an active ingredient. Lack of familiarity with a medicine name is not an acceptable reason for dispensing errors to occur.
As part of their licensing and operating requirements, New Zealand pharmacies are required to have access to reference pharmacopoeias, such as Martindale, which list synonyms for active ingredients and can be used to check the name of a medicine when in doubt. Pharmacists also use these reference texts when patients from other countries need assistance with their medicines, which invariably have different brand names to those available in New Zealand.
Medsafe has amended the search function on the Medsafe website so that data sheets and Consumer Medicine Information (CMI) can be searched for using any of the accepted synonyms for active ingredients. For example, while "furosemide" is the INN, a search using the synonym "frusemide" will also locate any medicines containing furosemide.
Medsafe is asking New Zealand sponsors to ensure consistent use of nomenclature between the medicine data sheet and the product label, with respect to specifying active ingredients.