Argatroban
Acova
Parenteral direct thrombin inhibitor (DTI)
Directly and reversibly inhibits thrombin. HEPATICALLY cleared — the DTI of choice in HIT with renal failure.
Indications
- •HIT (treatment + prophylaxis)
- •PCI in HIT patients
- •Alternative anticoagulation when heparin contraindicated
Dosing
| Context | Adult | Pediatric |
|---|---|---|
| HIT | 2 mcg/kg/min IV infusion, titrate to aPTT 1.5–3× baseline (0.5 mcg/kg/min if hepatic impairment/critically ill) | — |
Pharmacokinetics
Onset immediate IV. Half-life ~45 min. HEPATIC clearance — safe in renal failure, reduce in hepatic dysfunction.
Side effects
- !Bleeding
- !Prolongs INR (complicates warfarin transition)
Contraindications
- ×Active major bleeding
- ×Severe hepatic impairment (dose reduce)
Reversal / antidote
No specific antidote; short half-life — stop infusion; consider rFVIIa/PCC for life-threatening bleed
Clinical pearls
- ★ASRA neuraxial: DTIs have NO consensus timing — neuraxial generally AVOIDED while anticoagulated.
- ★DTI of choice in HIT + renal failure (hepatic clearance).
- ★Raises INR — when bridging to warfarin, overlap and interpret INR carefully (target higher).
Other drugs in Coagulation Related
- Heparin (unfractionated)
Activates antithrombin → inactivates IIa (thrombin) and Xa.
- Tranexamic Acid (TXA)
Reversibly binds plasminogen, blocking conversion to plasmin → preserves fibrin clot.
- Protamine Sulfate
Strongly basic (positive-charge) protein binds to highly acidic (negative-charge) heparin → inactive ionic complex → renal excretion. 1 mg protamine neutralizes ~100 units heparin.
- DDAVP (Desmopressin)
Selective V2 agonist (renal water retention + Factor VIII/vWF release from endothelial Weibel-Palade bodies). NO V1 vasopressor activity at therapeutic dose.
- Warfarin
Inhibits vitamin K epoxide reductase (VKORC1) → depletes reduced vitamin K → ↓ synthesis of factors II, VII, IX, X and proteins C/S. Full effect takes days (waits for existing factor decay).
- Enoxaparin
Antithrombin-mediated inhibition, weighted toward factor Xa over IIa (~3.8:1). More predictable than UFH — no routine monitoring.
- Dalteparin
Antithrombin-mediated factor Xa > IIa inhibition. Similar profile to enoxaparin; preferred LMWH in cancer-associated VTE (CLOT trial).
- Tinzaparin
Antithrombin-mediated factor Xa > IIa inhibition; higher mean molecular weight than enoxaparin (anti-Xa:IIa ~1.9:1).
Browse all classes: /reference/drugs
Suggested reading
- •Miller's Anesthesia, 9e
- •FDA package insert
- •ASRA regional anesthesia in the anticoagulated patient guidelines, 2018
