An international nonproprietary name (INN) is an official generic and nonproprietary name given to a pharmaceutical substance or an active ingredient, encompassing compounds, peptides and low-molecular-weight proteins (e.g., insulin, hormones, cytokines), as well as complex biological products, such as those used for gene therapy. INNs are intended to make communication more precise by providing a unique standard name for each active ingredient, to avoid prescribing errors. The INN system was initiated by the World Health Organization (WHO) in 1953.
Having unambiguous standard names for each pharmaceutical substance (standardization of drug nomenclature) is important because a drug may be sold under many different brand names, or a branded medication may contain more than one drug. For example, the branded medications Celexa, Celapram and Citrol all contain the same active ingredient whose INN is citalopram. The antibacterial medication known as co-trimoxazole as well as those under the brand names Bactrim and Septran all contain two active ingredients easily recognisable by their INN: trimethoprim and sulfamethoxazole.
The WHO publishes INNs in English, Latin, French, Russian, Spanish, Arabic, and Chinese, and a drug's INNs are often cognate across most or all of the languages, with minor spelling or pronunciation differences, for example: paracetamol (en) ' (la), ' (fr) and (ru). An established INN is known as a recommended INN (rINN), while a name that is still being considered is called a proposed INN (pINN).
Some examples of stems are:
- -anib for angiogenesis inhibitors (e.g., pazopanib)
- -anserin for serotonin receptor antagonists, especially 5-HT<sub>2</sub> antagonists (e.g., ritanserin and mianserin)
- -arit for antiarthritic agents (e.g., lobenzarit)
- -ase for enzymes (e.g., alteplase)
- -azepam or -azolam for benzodiazepines (e.g., diazepam and alprazolam)
- -caine for local anaesthetics (e.g., procaine)
- cef- for cephalosporins (e.g., cefalexin)
- -coxib for COX-2 inhibitors, a type of anti-inflammatory drugs (e.g., celecoxib)
- -grel- or -grel for platelet aggregation inhibitors (e.g., anagrelide, cangrelor, clopidogrel)
- -mab for monoclonal antibodies (e.g., infliximab); see Nomenclature of monoclonal antibodies
- -meran for messenger RNA products (e.g., tozinameran and elasomeran)
- -- or nab- for cannabinoid receptor agonists (e.g., cannabidiol, dronabinol, nabilone)
- -olol for beta blockers (e.g., atenolol)
- -pril for angiotensing converting enzyme (ACE) inhibitors (e.g., captopril)
- -sartan for angiotensin II receptor antagonists (e.g., losartan)
- -tinib for tyrosine kinase inhibitors (e.g., imatinib)
- -vastatin for HMG-CoA reductase inhibitors, a group of cholesterol-lowering agents (e.g., atorvastatin and simvastatin)
- -vir for antivirals (e.g., remdesivir and ritonavir)
- for antiretroviral protease inhibitors (e.g., darunavir)
- -ciclovir for bicyclic heterocycle antivirals (e.g., aciclovir and famciclovir)
Linguistics
Stems and roots
The term stem is not used consistently in linguistics. It has been defined as a form to which affixes (of any type) can be attached. Under a different and apparently more common view, this is the definition of a root, while a stem consists of the root plus optional derivational affixes, meaning that it is the part of a word to which inflectional affixes are added. INN stems employ the first definition, while under the more common alternative they would be described as roots.
Translingual communication
Pharmacology and pharmacotherapy (like health care generally) are universally relevant around the world, making translingual communication about them an important goal. An interlingual perspective is thus useful in drug nomenclature. The WHO issues INNs in English, Latin, French, Russian, Spanish, Arabic, and Chinese. A drug's INNs are often cognates across most or all of the languages, but they also allow small inflectional, diacritic, and transliterational differences that are usually transparent and trivial for nonspeakers (as is true of most international scientific vocabulary). For example, although ibuprofenum (la) has an inflectional difference from ibuprofen (en), and although ibuprofène (fr) has a diacritic difference, the differences are trivial; users can easily recognize the "same word". Although Ибупрофе́н (ru) and ibuprofen (en) have a transliteration difference, they sound similar, and for Russian speakers who can recognize Latin script or English speakers who can recognize Cyrillic script, they look similar; users can recognize the "same word". Thus, INNs make medicines bought anywhere in the world as easily identifiable as possible to people who do not speak that language. Notably, the "same word" principle allows health professionals and patients who do not speak the same language to communicate to some degree and to avoid potentially life-threatening confusions from drug interactions.
Spelling regularization
To facilitate the translation and pronunciation of INN, "f" should be used instead of "ph", "t" instead of "th", "e" instead of "ae" or "oe", and "i" instead of "y"; the use of the letters "h" and "k" should be avoided. Thus a predictable spelling system, approximating phonemic orthography, is used, as follows:
- ae or oe is replaced by e (e.g. estradiol vs. oestradiol)
- ph is replaced by f (e.g. amfetamine vs. amphetamine)
- th is replaced by t (e.g. levmetamfetamine vs. levo-methamphetamine)
- y is replaced by i (e.g. aciclovir vs. acyclovir)
- h and k are avoided where possible
Names for radicals and groups (salts, esters, and so on)
Many drugs are supplied as salts, with a cation and an anion. The way the INN system handles these is explained by the WHO at its "Guidance on INN" webpage.
Comparison of naming standards
Several countries had created their own nonproprietary naming system before the INN was created, and in many cases, the names created under the old systems continue to be used in those countries. As one example, in English the INN name for a common painkiller is paracetamol; the table below gives the alternative names for this in different systems:
{| class="wikitable"
|-
| International Nonproprietary Name (INN) ||
|-
| Australian Approved Name (AAN) || paracetamol
|-
| British Approved Name (BAN)|| paracetamol
|-
|Chinese Approved Drug Name (CADN) || 对乙酰氨基酚 (zh)
|-
| || acetaminophen
School of INN
The School of INN is a WHO International Nonproprietary Name Programme initiative launched in 2019, which aims to provide information to pharmacy, medical and health students, as well as health professionals and other stakeholders on how an INN is designed and constructed. Users can take self-administered courses using its free online learning platform.
See also
- Generic drug
References
Further reading
External links
- School of INN
