In 1921, insulin was discovered in Toronto. Its discoverers sold the patent to the University of Toronto for a token sum, famously a dollar, because they wanted it to be available to everyone who needed it.
A hundred years later, in November 2021, the World Health Organization published a report marking that anniversary. Its central finding: globally, one in every two people who need insulin for type 2 diabetes do not get it.
Insulin has been on WHO’s Model List of Essential Medicines for decades; the list itself dates to 1977. It is cheap to produce relative to many modern drugs. Nobody disputes that it is essential. And still, half of the people with type 2 diabetes who need it go without.
That tells you something important about access to medicines. The debate often focuses on which drugs should be on the list and what they should cost. Those questions matter. But for many essential medicines, the binding constraint is duller and harder to fix: whether the drug is actually on the shelf, in the right place, when the patient arrives.
A list is a promise, not a supply chain
The Model List of Essential Medicines is one of WHO’s most successful ideas. It gives countries a starting point for deciding which medicines to prioritise, and most countries have national lists based on it.
But a medicine on a list is not a medicine in a clinic. Between the two sit procurement, financing, quality control, storage, distribution, forecasting and the day-to-day management of stock in thousands of facilities. Any weak link produces the same result for the patient: nothing to dispense.
WHO has long estimated that nearly 2 billion people lack access to essential medicines. The number is striking, but it hides a crucial distinction. Some of those people cannot afford medicines that are available. Others cannot find them at all.
How stock-outs turn free into expensive
Here is the mechanism that quietly undermines many health reforms.
A government announces free medicines at public facilities. The patient arrives, is seen and receives a prescription. But the facility is out of stock. So the patient is sent to a private pharmacy nearby, where the same medicine is available, at a price.
The policy says free. The patient pays anyway.
This matters because medicines make up a large share of what households spend on health. WHO has reported that in developing countries, medicines account for between 20 and 60 percent of health spending, and that up to 90 percent of people buy their medicines out of pocket. A reform that abolishes consultation fees but cannot keep medicines in stock may do little to reduce household costs.
The uncomfortable incentive
Stock-outs are not just logistical failures. Sometimes they persist because someone benefits.
When public shelves are empty, nearby private pharmacies gain customers. In settings where health workers also have links to private outlets, the incentive to keep public stock reliable weakens. Researchers studying medicine supply in several countries have raised concerns about medicines intended for free public distribution leaking onto the private market.
None of this means that everyone involved is acting in bad faith. Most stock-outs come from underfunding, poor forecasting and weak logistics. But any honest diagnosis has to acknowledge that a broken public supply chain creates winners, and winners do not always push for repair.
Price still matters, especially for newer medicines
None of this makes price irrelevant. For newer medicines, such as some cancer treatments, biologics and modern insulin analogues, price is often the primary barrier. WHO’s insulin report identified high prices, low availability of human insulin and a market dominated by a small number of producers as the main obstacles.
Market concentration is a structural problem. When a few companies dominate supply, countries have limited leverage in negotiations and limited alternatives when supply is disrupted. Pooled procurement, where several countries buy together, and support for additional manufacturers, including in regions that currently import almost everything, can shift that balance.
What moves access, in practice
For health ministries and procurement agencies, several practical priorities follow.
- Measure availability, not just policy. Regular facility surveys of whether key medicines are actually in stock tell you more than the national list does.
- Fund the supply chain, not only the medicines. Warehouses, transport, information systems and trained supply chain staff are part of the cost of access.
- Make stock data visible. Real-time stock reporting lets managers redistribute medicines before shelves go empty, and makes persistent stock-outs harder to ignore.
- Buy together. Pooled procurement can reduce prices and improve reliability, especially for smaller countries.
- Protect medicine budgets. When health budgets are squeezed, medicine lines are often cut first, because the effects are delayed. Ring-fencing them prevents that.
Following one box of medicine
It helps to trace the journey of a single essential medicine from purchase to patient, because each link has its own failure mode. The sequence below is generic, but it will be familiar to anyone who has worked in a public supply chain.
Forecasting. Someone estimates how much will be needed next year. If historical consumption data is poor, or if past stock-outs suppressed demand, the forecast will be too low. A clinic that ran out for three months appears to have needed less.
Financing. The budget is approved, often late, sometimes smaller than requested. Medicines compete with salaries, and salaries usually win.
Procurement. Tenders are issued, bids evaluated, contracts signed. Delays of months are common. Low bids can mean low quality, and quality assurance capacity is often limited.
Storage and distribution. Medicines arrive at a central warehouse and move to regional stores, then to districts, then to facilities. Each step needs transport, storage, record-keeping and staff. Some medicines, such as insulin, need refrigeration throughout.
Facility management. At the clinic, stock must be counted, orders placed on time and expiry dates watched. This is frequently done by staff with other duties and little training.
Dispensing. Finally, the medicine reaches the patient, if all the previous steps worked.
A failure at any point produces the same outcome at the end: an empty shelf. And because the failure is usually invisible to the patient, the empty shelf is often blamed on the clinic that happens to be the last link.
The strongest counterargument
There is a strong case that focusing on public supply chains is misplaced, and it is worth taking seriously.
In many countries, the private sector already supplies a large share of medicines, through pharmacies and drug shops that are often closer, open longer and better stocked than public facilities. Rather than trying to fix slow public systems, the argument goes, governments should work with private supply: subsidising essential medicines through private outlets, regulating quality and prices, and paying pharmacies to dispense to insured patients. Some argue that public procurement has been tried for decades with limited success, and that market-based approaches deserve more attention.
This holds in part. Private outlets are a reality, and ignoring them leaves many patients unprotected. Partnerships with accredited private pharmacies, quality regulation and price controls on essential medicines can improve access, particularly in urban areas.
But the argument has limits. Private supply follows purchasing power, so it tends to be weakest in the poorest and most remote areas, where public supply matters most. Quality regulation of large numbers of small private outlets is hard, and substandard and falsified medicines are a real risk. And if patients pay out of pocket at private pharmacies, the financial protection problem remains. The more realistic position is that both public and private channels need to work, with public financing protecting patients regardless of where they collect their medicines.
Second-order effects
Antimicrobial resistance. When patients cannot get a full course of antibiotics, or buy partial courses from informal sellers, resistance becomes more likely. Unreliable supply is also a resistance problem.
Trust in primary care. Patients who repeatedly find empty shelves at public clinics stop going to them, bypassing primary care for hospitals or private providers. That weakens the part of the system meant to be the front door.
Chronic disease control. Conditions such as hypertension, diabetes, epilepsy and HIV depend on uninterrupted supply. Even short interruptions can undo months of control.
Health worker morale. Clinicians who diagnose correctly but cannot treat because of missing medicines experience frustration that contributes to burnout and attrition.
What this means for different decision-makers
For health ministries, the priority is to treat supply chains as core health system infrastructure, with dedicated budgets, trained professionals and performance targets for availability at facility level.
For finance ministries, medicine budgets are a poor place to find savings. Cuts appear small but cause stock-outs that shift costs to patients and to more expensive hospital care.
For facility managers, the practical tools include regular stock counts, timely ordering and clear escalation when stock-outs loom. Sharing stock between nearby facilities can prevent shortages.
For funders, support for supply chain systems, data and people may do more for access than donations of medicines, which can themselves disrupt local supply if poorly coordinated.
For clinicians, prescribing from the national essential medicines list where appropriate, and reporting stock-outs rather than quietly working around them, both help make the problem visible.
What to watch next
The essential medicines list will mark fifty years in 2027. Watch whether that anniversary focuses attention on availability, not just on which medicines are listed. Watch developments in regional manufacturing, which could reduce dependence on a small number of producers. Watch how cuts to international health funding affect supply of medicines that have long been donor-financed, such as those for HIV, tuberculosis and malaria. And watch whether countries begin to publish facility-level availability data regularly. What is measured publicly is harder to neglect.
What a patient cannot see
From the patient’s side, all of this is invisible. She knows only that the clinic said it had no stock, and that the pharmacy across the road did. She may reasonably conclude that the public system is incompetent, or that someone is profiting, or both. She will tell her neighbours.
That perception has consequences beyond a single prescription. It shapes whether people trust public services enough to return, whether they support taxes to fund them, and whether they believe government promises about free care. Stock-outs are not just a supply problem. They are one of the most frequent ways in which ordinary people experience the state failing them, and one of the reasons public health systems struggle to build the political support they need.
That is why availability data should be published, not just collected. Transparency turns an invisible failure into a public one, and public failures are more likely to be fixed.
None of this is new to pharmacists and supply chain professionals, who have warned about these weaknesses for decades. What is often missing is political attention. Supply chains rarely feature in ministers’ speeches, and nobody cuts a ribbon on a better forecasting system. Yet for a patient standing at a pharmacy counter, the forecast made eighteen months earlier decides whether she walks away with her medicine or with a prescription she cannot afford to fill.
The takeaway
The essential medicines concept has been one of global health’s quiet triumphs for nearly fifty years. But the gap between a medicine being declared essential and a patient actually receiving it is still enormous, as the insulin anniversary made clear.
Closing that gap is less about the list and more about logistics, financing and the incentives that keep shelves empty. It is unglamorous work. It is also where access is won or lost.
What is the essential medicine most often missing from the shelves where you work, and why? Share it in the comments.
