Weeknotes for the week finishing Friday, 2 January 2026.

After another hiatus, weeknotes are back. A lot has happened in the last six months. Nevertheless, these are weeknotes. What happened this week?

I’ve been reading about prescribing data, BNF codes, and dm+d codes in preparation for starting work on OpenPrescribing next week. We have a new team, a new codebase, a new GitHub project, and a new Slack channel.

I asked my colleagues what I should read to get up to speed and they suggested:

• Limitations of NHS England prescribing data
• Prescribing data: BNF codes
• What is the dm+d? The NHS Dictionary of Medicines and Devices

These took me to many, many pages on various NHS websites. The page I bookmarked, however, was English Prescribing Dataset (EPD) with SNOMED Code.

What have I learnt? Well, that an indication is a symptom that suggests that particular medical treatment is necessary. That prescribing data represent reimbursement claims from dispensing contractors; prescriptions issued and prescriptions dispensed are separate, but related. That BNF codes once formed a hierarchy; now they don’t, unless you’re the NHSBSA. That a thing called ePACT2 gives authorised users access to prescribing data. That ePACT2 relates to a thing called the One Drug Database. That the dm+d contains an alphabet spaghetti of terms: VTM, VMP, VMPP, AMP, AMPP. And that my colleagues were helping the NHS identify cost savings over eight years ago. Considerable cost savings: a theoretical maximum of £410 million over 12 months.

Time’s up!