04/11/2026
Anticoagulants in 60 seconds. 🩸 5 blood thinners, one simple picture each. Save this for your next pharm exam. 👇
🎯 First, the two targets. The whole clotting cascade funnels into two steps: Factor Xa turns prothrombin (II) into thrombin (IIa), and thrombin then knits fibrin into a clot. Every drug here blocks one of those two steps.
1️⃣ & 2️⃣ The heparins. Both work by supercharging antithrombin (AT), your body’s own clot cop.
Heparin (unfractionated): powers up AT to hit both IIa and Xa
Enoxaparin (LMWH): a smaller heparin that hits Xa far more than IIa
3️⃣ Apixaban. Handcuffs Xa directly, no antithrombin needed. Less Xa means less thrombin gets made, so prothrombin stays parked and less fibrin forms.
4️⃣ Dabigatran. Handcuffs thrombin (IIa) itself. No thrombin, no fibrin net, so fibrinogen never gets knitted into fibrin.
5️⃣ Warfarin. Switches off vitamin K. Normally the liver recycles vitamin K to switch on factors II, VII, IX and X (plus proteins C and S). Warfarin blocks the recycler (VKORC1), so new factors come out switched off. Fun fact: many rat baits work the exact same way, and the antidote is vitamin K1.
🧠 The name trick to remember it all: “-xaban” blocks Xa, “-gatran” blocks IIa.
That’s the whole class in one scroll. Save it and share it with your study group. 📚
Approved by Dr. Duncan Houston, emergency vet ✅
⚠️ Educational for clinical learners. Always follow current drug references and dosing guidance.