How the WHO Essential Medicines List Is Actually Chosen

The World Health Organization does not pick essential medicines by popularity or by which drugs are newest. An independent expert committee meets every two years, works from applications that anyone can submit, and judges each candidate against three questions: does the evidence show it works, is it acceptably safe, and does it deliver value at a comparative cost a health system can bear. Medicines that clear all three, for conditions that matter at a population level, make the list. Everything else, however promising, does not.

What the list is trying to answer

WHO defines essential medicines as those that satisfy the priority health care needs of a population. That framing does a lot of work. The point is not to crown the best drug ever made for a disease. It is to identify what a health system should stock so that most people, in most settings, can be treated effectively and safely at a price the system can sustain. The first Model List appeared in 1977 with roughly 200 medicines, according to WHO's fact sheet on essential medicines. A separate list for children followed in 2007. The 2025 revision, its 24th edition, holds 523 medicines for adults and 374 for children, per WHO's announcement of the update.

Who actually decides

The decisions rest with the WHO Expert Committee on the Selection and Use of Essential Medicines. Members are drawn from WHO's expert advisory panels for their clinical and technical expertise, with deliberate attention to geographic and gender balance so that experience from low, middle, and high income settings is represented. Members disclose interests that could bias their judgment. The committee's role is advisory: it recommends additions, amendments, and deletions, and WHO adopts the revised lists.

The naming can confuse. The committee that met in Geneva from 5 to 9 May 2025 was the 25th such meeting, and it produced the 24th edition of the main list. It reviewed 59 applications that cycle.

Where the candidates come from

This is the part most people miss. WHO does not go shopping for drugs. The list is application driven. A pharmaceutical company, a professional society, a WHO department, a clinician, even an individual can submit a structured application to add a medicine, change how it is listed, or remove it. The applicant carries the burden of assembling the evidence and making the case.

The three tests

For each application the committee weighs the same considerations, set out in its terms of reference: disease prevalence and public health relevance, scientific evidence of efficacy and safety, and comparative cost and cost-effectiveness.

Effectiveness means real clinical benefit shown in credible trials, not a plausible mechanism or a surrogate marker alone. Safety means the harms are characterized and acceptable for the benefit on offer. The third test, comparative cost, is where the Model List differs most from a national regulator's approval decision. A medicine can be fully approved and still fail the essential test if a cheaper option delivers similar benefit, because the committee compares each candidate against what is already listed. Cost is not a tiebreaker applied at the end. It is weighed alongside the clinical evidence throughout.

Decided in the open

The process is unusually transparent for a body with this much influence. Applications are posted on WHO's website for public review and comment before the meeting. The application itself, the expert peer reviews, comments from WHO technical departments, and submissions from outside bodies are all published. Anyone can read the case for and against a given medicine and see how the committee reasoned. That openness is a deliberate defense against the perception that a closed panel is quietly steering global demand.

Core, complementary, and what "essential" does not mean

The list is not flat. It separates core items, the most cost-effective options for major health problems that need little extra infrastructure, from complementary items that require specialized training, diagnostics, or monitoring, or that carry a less favorable cost-benefit profile. The committee also maintains the AWaRe classification of antibiotics (Access, Watch, Reserve) to steer prescribing toward stewardship and slow resistance.

Two cautions belong here, stated plainly. First, "essential" is a system-level judgment, not a ranking of the best available therapies for one person, and it does not replace a clinician's decision about a particular patient. Second, the Model List is a model. More than 150 countries maintain their own national essential medicines lists, adapting WHO's template to local disease burden, budgets, and infrastructure. The WHO list informs procurement, insurance and reimbursement schemes, donations, and local production, but each country decides what it can actually deliver.

Reading the list this way changes what a listing tells you. It is not a prize for the most advanced molecule. It is a signal that, on the published evidence, a medicine has earned its place in a system meant to treat a population well and affordably.

This article is educational and is not medical advice.