International Drug Safety Monitoring Systems Explained

Every time someone takes a medicine, there’s a quiet system working behind the scenes to watch for problems. It doesn’t make headlines. It doesn’t show up on TV ads. But when a new side effect shows up in a country halfway across the world, this system is the first to notice - and the only thing standing between a safe drug and a public health crisis.

How the Global Drug Safety Net Works

The backbone of international drug safety is the WHO Programme for International Drug Monitoring (a global network coordinated by the World Health Organization to collect and analyze reports of adverse drug reactions from over 170 countries). It started in 1968, after the World Health Assembly realized that drugs used by millions could have hidden dangers that only show up after widespread use. Back then, the only way to find out was to wait for doctors to report unusual side effects. Today, that system has grown into something far more powerful.

At the center of it all is VigiBase (the global database of individual case safety reports managed by the Uppsala Monitoring Centre, containing over 35 million reports as of 2023). Every time a doctor, pharmacist, or even a patient reports a bad reaction to a medicine - whether it’s a rash, liver damage, or a sudden heart rhythm problem - that report gets added to VigiBase. These aren’t just random notes. Each report follows strict rules: the drug name is coded using WHODrug Global (a standardized dictionary with over 300,000 medicinal product names across 60+ therapeutic classes), the reaction is classified with MedDRA (a medical terminology system with 78,000+ standardized terms organized into 27 organ systems), and the data is sent electronically using the E2B(R3) (an international standard for electronic transmission of adverse event data) format.

It’s not just about collecting reports. It’s about finding patterns. A single report of a rare side effect means little. But if five doctors in five different countries report the same issue with the same drug within a few months, that’s a signal. That’s when the system kicks into high gear. The Uppsala Monitoring Centre (the WHO Collaborating Centre responsible for managing VigiBase and conducting global signal detection) uses advanced algorithms - now boosted by artificial intelligence - to spot these patterns. In 2023, AI helped reduce false alarms by 28%, making the system faster and more accurate.

Regional Systems: EU, U.S., and Beyond

Not every country plays by the same rules. The European Union’s EudraVigilance (a mandatory, legally binding pharmacovigilance system managed by the European Medicines Agency with 98% electronic reporting and 1.2 million new reports annually) operates like a tightly regulated machine. Pharmaceutical companies in the EU are legally required to report adverse events within 15 days. The Pharmacovigilance Risk Assessment Committee (PRAC) (the EU body responsible for evaluating drug safety signals and making regulatory decisions) has a 60-day deadline to review urgent signals - and they meet it 92% of the time. That speed saves lives.

The U.S. FDA Adverse Event Reporting System (FAERS) (a voluntary reporting system that receives around 2 million reports per year and contributes data to VigiBase) is different. It’s open to anyone - patients, doctors, pharmacists, even drug companies. There’s no legal requirement for timely reporting. That means the data is rich in volume but messy in timing. Still, FAERS has helped uncover serious risks, like the link between certain diabetes drugs and pancreatitis.

And then there’s the rest of the world. While the EU and U.S. have robust systems, many low-income countries struggle to even collect basic data. In Sweden, healthcare workers report 1,200 adverse events per 100,000 people each year. In Nigeria, it’s 2.3. That’s not because Swedes have more side effects - it’s because they have better reporting systems. The WHO Global Benchmarking Tool (a framework assessing national pharmacovigilance systems across four maturity levels) found that 28% of countries still have no formal system at all. Even among those that do, many lack trained staff, funding, or internet access to submit reports.

Why Some Countries Are Left Behind

The gap isn’t just about money - though that’s a big part of it. High-income countries spend about $1.20 per person on pharmacovigilance each year. Low-income countries spend $0.02. That’s not enough to hire trained pharmacovigilance officers, buy software, or even keep computers running in rural clinics.

Training is another hurdle. WHO recommends 40 hours of specialized training for pharmacovigilance staff. A 2022 survey across Southeast Asia found that 68% of officers had received less than 15 hours. Without proper training, reports are incomplete, misclassified, or never filed at all.

Technology helps, but it’s not a magic fix. Ethiopia, for example, cut its reporting time from 90 days to 14 after adopting the Pharmacovigilance Monitoring System (PViMS) (a web-based tool developed by MTaPS to enable real-time reporting from health facilities). But only 35% of health facilities there still submit regular reports - because many have no stable internet connection. In rural areas, reports are still written on paper and mailed in, sometimes taking months to reach the capital.

And then there’s the problem of trust. In some countries, patients and doctors fear reporting side effects will lead to lawsuits, stigma, or even the withdrawal of a medicine they rely on. That silence hides risks.

The Hidden Power of Global Data

This system isn’t just about catching bad drugs. It’s about saving lives in ways you’d never expect.

Take Dengvaxia, the dengue fever vaccine. In 2017, health workers in the Philippines reported a strange pattern: children who had never had dengue before got severely ill after vaccination. That signal didn’t come from a lab in Europe or a study in the U.S. It came from a clinic in Manila. Because the WHO system was in place, that report was quickly shared globally. Within months, the vaccine’s use was restricted in several countries. Without that global network, thousands more children might have been harmed.

Or consider the rise in liver injuries linked to certain herbal supplements. These aren’t regulated like prescription drugs. But when reports started piling up in VigiBase from Brazil, South Africa, and Australia, regulators took notice. That led to new warnings - and in some places, outright bans.

The system also helps when drugs are used in new ways. A medicine approved for high blood pressure might be prescribed off-label for anxiety. If enough people report side effects in that context, the system picks it up. That’s how we learn what a drug can really do - not just in clinical trials, but in real life.

What’s Changing Right Now

The system is evolving. In 2024, Zanzibar joined the network. Ukraine restarted its national center after war disrupted operations. Yemen, despite years of conflict, reactivated its reporting system in late 2022.

One of the biggest changes coming is the ISO IDMP (International standards for identifying medicinal products across 100+ data elements, planned for full implementation by 2025). Right now, the same drug might be listed under 10 different names in different countries. That makes it hard to match reports. IDMP will fix that. Once it’s in place, a report from India about a drug called “Metformin 500mg” will be automatically linked to the same drug in Germany, Brazil, or Canada - even if it’s sold under a different brand name.

Public access is also improving. VigiAccess (a free public portal launched in 2015 that lets anyone search anonymized data from VigiBase) has had over 12 million visits. Patients, researchers, and even journalists now use it to check if a drug they’re taking has been linked to unusual side effects.

And the money is flowing. The global pharmacovigilance market is expected to hit $13 billion by 2030. Big pharma now spends millions on dedicated safety teams - up from 150 full-time staff per company in 2018 to 250 today. That’s because regulators are watching closer than ever.

What’s Still Broken

Despite progress, the system has deep flaws. One of the biggest? Inconsistent ways of judging whether a drug actually caused a side effect. A 2023 study found that EU and U.S. experts agreed on causality in only 63% of the same case reports. That means the same patient report could be labeled “likely caused by the drug” in one country and “unrelated” in another. That inconsistency delays action.

And while AI helps, it’s not perfect. Algorithms can miss rare events if they’re too rare. They also can’t understand cultural context - like why a certain herbal remedy is mixed with a prescription drug in one region but never in another.

Most worrying: 42% of low- and middle-income countries still don’t have a functional system that meets WHO’s minimum standards. That means drugs used in those countries are flying blind. No one’s watching. No one’s listening.

Don’t assume safety is guaranteed. Just because a drug is approved doesn’t mean it’s risk-free. The system works best when people report - even small, weird side effects. A headache after taking a new pill? A rash that won’t go away? A sudden change in mood? Write it down. Tell your doctor. Submit it. That one report could be the thread that pulls back the curtain on a global problem.

Frequently Asked Questions