The WHO's essential medicines list has grown from 208 drugs to 523
Since 1977 the World Health Organization has published a list of the medicines a health system most needs: effective, safe and good value. More than 155 countries have based their own national lists on it. The first edition held 208 medications; the 24th, released in September 2025, recommends 523.
The list is revised every two years, and its growth tracks both new drugs and changing priorities. The 14th edition in 2005 had 306 entries, the 19th in 2015 had 410, and the 22nd in 2021 reached 479. National versions derived from it range from 334 to 580 medicines, and rich and poor countries alike use it as a template.
Entries are split into two tiers. Core items are judged the most cost-effective answers to major health problems and can be used without much extra equipment or staff. Complementary items, about a quarter of the list, either need specialist infrastructure, such as trained providers or diagnostic kit, or offer less benefit for their cost; some drugs appear in both tiers. Most listed medicines are available as generics, but a patent does not rule a drug out.
Antibiotics are sorted by how much resistance they risk breeding. One group covers broad-acting drugs with lower resistance potential, such as amoxicillin combined with clavulanic acid. A second holds classes more likely to select for resistant bacteria, including many of the highest-priority critically important antimicrobials. A third is meant to be held back for infections that are confirmed or suspected to be multi-drug-resistant. A separate list for children up to twelve was created in 2007 so that suitable formulations would be considered systematically; it is now in its 10th edition, and every item on it also appears on the main list.
How the choices get made has drawn scrutiny. A study in BMJ Global Health examined targeted cancer drugs proposed between 2015 and 2021 and found 22 of 54 indications recommended. Of 11 cancer indications approved in 2019 and 2021, only 45.5 percent met a European oncology benefit scale's criteria, and some drugs were eventually accepted without new survival evidence. Lower prices and wider treatment options seemed to weigh heavily, and the authors called for clearer adherence to the WHO's own criteria.
Source: WHO Model List of Essential Medicines
