Feature Christmas 2025: Black Mirror

How the BNF has grown in size and weight over decades

Jamie Hayes, Steven D Williams, Paul Gimson, et al

BMJ 2025; 391 doi: https://doi.org/10.1136/bmj.r2574 (Published 16 December 2025)Cite this as: BMJ 2025;391:r2574 

Jamie Hayes and colleagues describe the history and sometimes personal significance of a go-to reference point for healthcare professionals in the UK and beyond

Everyone has a favourite edition of the British National Formulary (BNF), an edition, smell, and colour that takes them back to a specific time and place—that gastro ward, dispensary, or outpatient clinic, or a training moment, patient, or colleague (box). Those editions and colours are memorable for a reason. The colour of each book reassured clinicians at a quick glance that they were using the most up-to-date drug information available at the time.

Fig 1

One of us (JH) recently rescued an almost entire collection of BNF editions. The books had been collected by palliative care pharmacist Vanessa Skingle and, when she retired, they had been earmarked for removal and disposal. JH heard about their plight and sought permission to re-house the collection.

The condemned books weren’t quite in the skip, but were pretty close. The rescue took place in Penarth, South Wales. Poignantly, this was 400 metres from the early family home of Owen Wade, one of the founding fathers of clinical pharmacology and therapeutics in the UK who oversaw the modernisation and relaunch of the BNF in 1981.1

Here was 45 years’ prescribing and therapeutics history, colours and designs side by side. Special anniversary editions of the BNF have included a “25” in silver on the cover and spine of the March 1993 edition, a “50” emblazoned in gold on the cover and spine of the September 2005 edition, and the NHS rainbow and “Thank You” on the cover and spine of the 80th and 81st editions to remember NHS efforts during covid-19.

The BNF is a comprehensive register of all medicines currently available in the UK. It is the gold standard source of guidance for prescribers and dispensers, predominantly (but not solely) in the UK,2 and the model for many of the national formularies of other countries. Published jointly by BMJ and Pharmaceutical Press, the publishing arm of the Royal Pharmaceutical Society, it is now updated every March and September.

The BNF was first published in 1949 as a direct descendant of the National War Formulary, which was itself developed in 1939. Writing in The BMJ in 1993, Wade commented that this original BNF did a good job for about 20 years, then “sickened and died” in 1976. The format we recognise today was reborn in 1981.1

The first edition (BNF No 1) of the new British National Formulary was bound in ultramarine cloth and distributed throughout the NHS in February 1981. The bespoke “pocket” size (215 mm × 130 mm) was changed to a standard A5 size (210 mm × 148 mm) in 2015, together with the introduction of a bright new colour palette,3 producing the iconic design we recognise today. At its peak, half a million copies were printed.

Fig 2

The book was originally designed to fit in the pocket of a doctor’s white coat. It grew over time to keep up with demand for more guidance about an expanding range of medicines, and this outweighed the need for it to be a snug sartorial fit. In his 1993 account, Wade commented that “the 25th edition may not have increased much in girth . . . but has grown in stature.”

Fig 3

The convenient size of the BNF often resulted in it being removed from wards and clinics as various medical and surgical firms visited and left with the ward copies in their pockets. It was not uncommon to see BNFs chained to nursing stations and drug trolleys to prevent this.

To look at how the weight and size of the BNF has changed since 1981, we weighed and measured 14 editions of the BNF, using a Salter kitchen scale and a standard metric ruler. We verified our figures by repeated measurements until we arrived at a consensus.

The first edition, published in 1981, weighed 331 g and had a width of 16 mm. The 25th special edition that Wade referred to weighed 473 g, with a width of 20 mm. BNF 69, published in March 2015, was the final edition of the pocket sized version, and measured 215 mm × 130 mm, while BNF 70, published in September 2015, was the first of the A5 size, measuring 210 mm × 148 mm. The first BNF to weigh more than 1 kg was BNF 79, published in March 2020.

The 90th edition of the BNF, which covers September 2025 to March 2026, weighs 1170 g and has a width of 43 mm. Each millimetre makes for thousands more words and figures, lovingly added so that clinicians can enjoy easy entry into the ever evolving landscape of pharmaceuticals.

Fig 4

From 1981 to 2025 the BNF has seen a 353% increase in weight and a 269% increase in width. It has become so large, with so many pages of text, that it requires paper that is very thin but also durable and strong. Only two printers in Europe can work to its specifications, the same printers who also produce copies of the Bible.

As we focus more on shared decision making and concerns about overdiagnosis and overprescribing, the expansion of the BNF to accommodate new medicines and new uses for current medicines might give us pause to think about the effort we put into prescribing medicines without reciprocal advice and guidance on how to stop them.

Today, when medical and pharmacy students interact with the BNF in interprofessional workshops, they often struggle to navigate the hard copies, and are much more comfortable using the app. The National Institute for Health and Care Excellence stopped supplying print copies of the BNF to the NHS in England in 2023, which was probably the right decision. Given the pace at which evidence is now produced, the hard copy was often out of date or at odds with current practice on the day it was printed.

Over the past 76 years, the BNF has changed, evolved, and grown. The editions constitute many decades of prescribing and therapeutics history, and represent a treasure trove that requires a special place in medical history—not in a municipal recycling centre.

Fig 5

Our favourite BNFs

Everyone has their favourite edition of the formulary.

For JH it is the 18th edition from 1989. “It was issued to me in my second year at the Welsh School of Pharmacy, Cardiff. Those earlier editions contained a formulary section towards the back with formulas for many extemporaneous preparations, including diamorphine and cocaine elixir, menthol and eucalyptus inhalation, phenol gargle, and belladona mixture.”

For SW, it is the 22nd edition. “The BNF has been my bible for 34 years and in my formative years between 1991 (edition 22) and 2005 (edition 50), I used to lovingly fit each new edition inside my British racing green leather book cover. The cover was given to me in my pre-registration year, embossed with ‘Diprivan’ and ‘ICI’ and I never went to the wards without it. It was much admired by doctors, nurses, and pharmacists alike. My favourite edition of the BNF will be number 100 as, if it is still published twice a year, that is the year I plan to retire—2030!”

For PG it was the March 1993 edition. “The 25th edition of the BNF will always matter to me because it was the one I lived with, learnt from, and practically memorised during my pre-registration year. It was the book I read page by page, day after day, tagging every chapter until it was more Post-it than paperback. In the pharmacy, my colleagues would flip it open at random and quiz me, and I’d almost always know the answer because by then I’d absorbed it like scripture. I was in the first year to sit the new registration exam, so the 25th edition wasn’t just a reference text, it was my safety net, my training ground, and the book that helped me become a pharmacist. And yes . . . it’s still in the attic.”

For MT it is the 40th edition. “It came out in the year I started as a junior doctor in City Hospital in Birmingham (2000-01). I used to carry it with me everywhere, together with the Oxford Handbook of Medicine, in my white coat pocket. I am ashamed to say that we also used it to prop open doors in our hospital accommodation when we held monthly payday parties.”

NF weights and widths (measured with kitchen scales and ruler)

BNF edition	Date	Width (mm)	Weight (g)
1	1981	16	331
10	1985	17	372
20	Sep 1990	19	434
25	Mar 1993	20	473
30	Sep 1995	23	521
40	Sep 2000	21	480
50	Sep 2005	24	562
60	Sep 2010	26	639
69	Mar 2015-Sep 2015	26	637
70	Sep 2015-Mar 2016	30	814
78	Sep 2019-Mar 2020	38	999
79	Mar-Sep 2020	39	1025
80	Sep 2020-Mar 2021	39	1057
90	Sep 2025-Mar 2026	43	1170