The medicine that saves lives if you get it right — and harms if you don't

If you've ever had a relative with atrial fibrillation, a mechanical heart valve, or a blood clot in the leg, you've probably heard the words "blood thinner." These medicines, oral anticoagulants, are some of the most effective tools we have for preventing strokes and dangerous clots. They are also, ironically, one of the most common causes of serious medication errors in hospitals worldwide.

That contradiction is what pulled me into this research. OACs sit in an unusual space: too little of the drug, and a patient can develop a stroke; too much, and they can bleed dangerously. Getting the balance right depends heavily on one thing that's rarely talked about, how well the doctors, pharmacists, and nurses prescribing, dispensing, and monitoring these drugs actually understand them.

So, together with my PhD supervisor, Dr. Segun Showande, I set out to answer a simple but under-studied question: How much do Nigerian healthcare professionals really know about oral anticoagulants, how do they feel about prescribing and using them, and does that translate into good clinical practice?

What we did

Over ten months, we surveyed 687 healthcare professionals across Nigeria (physicians, pharmacists, and nurses) using both an online questionnaire and paper forms handed out in hospitals and pharmacies. We asked about their knowledge, their attitudes, and their practices using a series of questions.

What we found

Most professionals had only "fair" knowledge, a positive attitude, and good practice, but hidden inside those averages were some worrying gaps.

• 9 in 10 correctly knew that bleeding is the most serious side effect of these drugs.
• But only 4 in 10 knew that the newer "DOAC" anticoagulants (drugs like rivaroxaban and apixaban) are actually risky in patients with poor kidney function,  a gap that matters, because using the wrong dose in someone with kidney disease can cause serious harm.
• Familiarity with different DOACs was also lopsided, as almost everyone had heard of rivaroxaban, but very few professionals recognised apixaban or edoxaban, even though these are increasingly used worldwide.
• Nurses scored significantly lower on knowledge and attitude than pharmacists. This isn't a criticism of nurses; it reflects a training gap, since anticoagulant management is rarely covered in depth in standard nursing curricula.
• The single strongest predictor of doing well? Having received prior training on anticoagulants. People who had specific training scored meaningfully higher on both knowledge and practice; a strong, actionable signal.

Why this matters beyond Nigeria

It would be easy to read this as "a Nigeria problem," but similar knowledge gaps have shown up in studies from Sudan, Syria, and even higher-income countries like Canada and Qatar, just to different degrees. What makes the Nigerian context distinct is the scale of the stakes: high patient-to-doctor ratios, limited access to routine INR testing in many facilities, and a healthcare workforce that is being asked to manage increasingly complex medications with limited continuing education support.

The encouraging part of our findings is that the fix is not complicated or expensive. It isn't about new technology or major infrastructure. It's about structured, practical training and making sure that training reaches nurses and general physicians, not just specialists.

What we think should happen next

Based on what we found, we've suggested a few concrete steps for hospitals, universities, and regulators:

1. Build anticoagulation training into medical, pharmacy, and nursing curricula as core content, given how common these drugs are.
2. Bring pharmacists more actively into anticoagulation clinics. Pharmacists in our study showed strong knowledge of drug interactions and monitoring. That expertise is currently underused in many Nigerian hospitals.
3. Make continuing education mandatory, not optional, for professionals already in practice because our data show it works.
4. Target DOAC-specific education, since this is where the biggest knowledge gaps sit, and DOAC use is only going to increase.

A personal note

Running this study nationwide was, frankly, exhausting. But every time I think about a patient somewhere in Nigeria whose warfarin dose is being adjusted by someone who's genuinely unsure whether grapefruit interacts with it or whether it's safe to double up after a missed dose, the "why" becomes obvious again.

Good anticoagulant care isn't just about having the drug available. It's about the person handing it to you knowing exactly what it does and what it doesn't.

Read the full open-access paper here: [ https://doi.org/10.1186/s12875-026-03474-4]