Many of the drugs we use in psychiatry are referred to by outdated or confusing names, for instance ‘second generation’ (or worse still, ‘atypical’) antipsychotic, or terms such as ‘noradrenergic and specific serotonergic antidepressants’ and ‘noradrenergic reuptake inhibitors’ for drugs for depression. Moreover, new drugs that are developed are referred to according to these disorder-based categories and then found to be effective in another disorder. Sometimes drugs called ‘antipsychotics’ are prescribed in bipolar disorder and those called ‘antidepressants’ are routinely prescribed for anxiety disorders. This causes confusion for patients and may affect adherence.
A system of naming drugs on the basis of their action on brain targets was proposed by international experts in the field under the leadership of the European College of Neuropsychopharmacology (ECNP). In 2008, a task force was set up for psychotropic nomenclature comprising representatives from five international organisations: ECNP, the American College of Neuropsychopharmacology, Asian College of Neuropsychopharmacology, International College of Neuropsychopharmacology and the International Union of Basic and Clinical Pharmacology. The group of experts tasked itself “to examine ways of improving the current nomenclature in psychopharmacology”. Specifically, the new nomenclature was to: (a) be based on contemporary scientific knowledge; (b) help clinicians to make informed choices when working out the next ‘pharmacological step’; (c) provide a system of naming that does not conflict with the actual use of medications; (d) be future-proof to accommodate new types of compounds.
A goal of this system is to help clinicians to start appropriate treatment and then to help guide the next neuropsychopharmacological treatment step when facing drug intolerance, partial response or treatment resistance. Another crucial goal is to help patients to understand and accept a prescribed treatment for a condition that is different from its initial indication, by explaining its actions in the brain. After intensive work, the task force came up with a proposal to create a pharmacologically driven (rather than indication-based) nomenclature, embedding contemporary neuroscience to better help prescribers understand how medicines act.
After presentation at a number of international scientific meetings, with attendees consulted for their feedback, the first version of this naming system, which is called neuroscience-based nomenclature (NbN), was agreed by the expert committee and published first as a book and then as a user-friendly, easily searchable phone app in 2014. The naming system classifies the drugs according to pharmacological targets that are all well known to clinicians and includes terms such as ‘serotonin’, ‘dopamine’, ‘acetylcholine’ and ‘gamma-aminobutyric acid’, and then specifies their mode of action in standard terms such as ‘agonist’, ‘antagonist’, ‘reuptake inhibitor’ and ‘enzyme inhibitor’. These are established, known terms that characterize putative mechanisms of action. It is hoped that such information will help decrease the occurrence of irrational polypharmacy.
As well as the pharmacological information, there is information for each drug on approved indications, as well as additional conditions in which efficacy has been shown by randomized controlled trials or substantial clinical data, albeit without an official indication for these (often because pharmaceutical companies were not interested or it was not financially viable to obtain one. Side effects are summarized with a focus on the most common and the most potentially dangerous effects. A helpful addition is the inclusion of practical notes, which embody the combined wisdom of the international expert committee and highlight, for instance, important drug interactions, metabolic issues and specific warnings. Brief information on the neurobiology of each drug is also given for those who wish to delve further into the biological basis for the nomenclature.
Since NbN has been available, more than 25,000 clinicians worldwide have downloaded and are using the app (figures from October 2017). There is now an update, NbN2, which includes more drugs and updated information. A child and adolescent version, compiled by leading clinicians in child and adolescent mental healthcare (NbN C&A), is also available. Each of the sections (pharmacology, mode of action, indications, efficacy and side effects, and practical notes) can be searched, and swiping left will reveal drugs with similar properties.
NbN is an ongoing project: it is updated each year with new medications being introduced to the market and the emergence of novel data. Comments and suggestions for items to be included can be provided through the ‘Send Feedback’ option, available on the right sweep function of the app. Many top psychiatry journals now expect submitting authors to use this new terminology.
How will NbN help clinicians and their patients in psychiatry?
The app is helpful in many ways. It will help to classify newer antipsychotics more accurately rather than them just referred to incorrectly as ‘atypical’. Moreover, for instance from a clinician’s point of view, if there was a patient with an anxiety disorder who had been prescribed a serotonin reuptake inhibitor, as many are, and found a particular side effect unacceptable, a quick search on the app for drugs with a similar target but different mode of action would give a list, from which an alternative with a lower risk of inducing that known side effect could be selected. Or if someone with severe depression was partially responding, those drugs which have an indication for augmenting this response could be found quickly by searching for, say, ‘adjunct’ if this was to be considered before switching strategies.
From the patient’s point of view, for example to many people with depression, it would be helpful and reassuring if they knew that the treatment strategy was to focus on restoring serotonin function in the brain, and therefore the name for the drug a clinician had prescribed, a serotonin receptor antagonist, would be informative and readily explained at home.
At present, the committee is working on NbN-P, a similar app for patients and carers. This will contain much of the information in NbN2, with appropriately nonscientific language, and will allow patients to better understand the treatments they are taking, and thus increase their motivation for compliance.
The NbN-2 and NBN C&A apps are available free via Google Play and the iOS app stores. More information about the nomenclature and the task force, and an introduction to searching the app can be found on the official NBN website (www.NbN2.com).