[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Pharmacology](https://durgical.com/en/pharmacology/) › [Antiplatelet drugs](https://durgical.com/en/pharmacology/classes/antiplatelet-drugs/) › Vorapaxar

# Vorapaxar

## Antiplatelet drugs?

Antiplatelet drugs

An oral PAR-1 (thrombin receptor) antagonist added to aspirin or clopidogrel after MI or in peripheral artery disease; it has been discontinued in the US.

Updated Nov 1, 2026

## Quick facts

**Group**
[Antiplatelet drugs](https://durgical.com/en/pharmacology/classes/antiplatelet-drugs/)

**Target**
Protease-activated receptor 1 (PAR-1), the platelet thrombin receptor

**Used for**
Reduction of thrombotic events

**Key effects**
Bleeding · Anaemia

**Monitor**
Signs of bleeding · Haemoglobin

**ATC**
B01AC26

No doses: the clinician sets them by the current guideline.

On this page

- The basics Mechanism of action
- Indications
- Adverse effects
- Pharmacokinetics
- Memory aid

- Safety Contraindications
- Key interactions
- What is monitored
- Administration and safety
- Pregnancy and breastfeeding
- Nursing care

- Study Test yourself

- Connections Connections

## Mechanism of action

◎**Protease-activated receptor 1 (PAR-1), the platelet thrombin receptor**Vorapaxar

ⓘ The figure shows vorapaxar bound to human PAR-1 (the crystal uses a lysozyme insert to stabilise the receptor).

**Target in 3D:** Protease-activated receptor 1 (PAR-1), the platelet thrombin receptor. PDB structure 3VW7 (RCSB PDB, public domain). [View the structure at RCSB PDB](https://www.rcsb.org/structure/3VW7) · Drag to rotate · pinch to zoom

Thrombin activates platelets by cutting PAR-1. Vorapaxar is a competitive PAR-1 antagonist that blocks thrombin-induced platelet activation and aggregation. It binds so tightly that its effect can last up to 4 weeks after the last dose.

- Thrombin normally activates platelets through PAR-1
- Vorapaxar occupies PAR-1
- Thrombin-induced aggregation is blocked
- Tight binding keeps the effect for weeks

## Indications

- Reduction of thrombotic events after myocardial infarction, with aspirin and/or clopidogrel [Myocardial Infarction (Heart Attack) →](https://durgical.com/en/conditions/myocardial-infarction/)
- Reduction of thrombotic events in peripheral artery disease [Peripheral artery disease →](https://durgical.com/en/conditions/peripheral-artery-disease/)

## Adverse effects

### Common

- Bleeding, including nosebleeds
- Anaemia (tiredness, weakness, pallor)

### Serious (rare, important)

- Severe or fatal bleeding, including intracranial haemorrhage
- Blood in urine, vomit or stools

## Contraindications

- History of stroke, transient ischaemic attack or intracranial bleeding
- Active pathological bleeding, such as a bleeding ulcer

## Key interactions

**Anticoagulants (warfarin, heparins, fondaparinux, rivaroxaban, dabigatran)**
Add to the bleeding risk

**NSAIDs, SSRIs and SNRIs**
Add to the bleeding risk

**St John's wort and drugs that strongly change CYP3A4 activity**
Can change vorapaxar levels

## What is monitored

- Signs of bleeding
- Haemoglobin
- Neurological symptoms (headache, weakness)

## Administration and safety

- Oral tablet, always together with aspirin and/or clopidogrel
- Before surgery or dental work, the team is told: the effect lasts weeks after stopping
- Discontinued in the US; availability elsewhere varies

## Pregnancy and breastfeeding

A pregnancy, plans for it or breastfeeding are reported to the doctor; the label information is limited.

## Nursing care

- Screen for previous stroke, TIA or brain bleeding before the first dose
- Teach signs of bleeding and to seek help at once
- Review all medicines, including NSAIDs, antidepressants and herbal products
- Explain that bleeding risk continues for at least 4 weeks after stopping

## Pharmacokinetics

**Absorption**
Oral; about 90% bioavailable, rapid onset

**Metabolism**
Liver, by CYP3A4

**Half-life**
About 3–4 days; the effect on platelets can last up to 4 weeks

## Memory aid

«VORA-PAR-ax blocks the PAR»: thrombin's platelet receptor; never after a stroke.

## Test yourself

Think of the answer, then tap the question to see it.

## Which receptor does vorapaxar block?

PAR-1, the thrombin receptor on platelets.

## Which history rules it out?

Stroke, TIA or intracranial bleeding.

## Why does its effect last weeks after stopping?

It binds PAR-1 very tightly and has a long half-life.

[Add to my cards (3)](https://durgical.app/estudiar/?add=/en/pharmacology/vorapaxar/)

[More Pharmacology questions →](https://durgical.com/en/practice/?f=pharmacology)

## Connections

## Related drugs 3

- [Clopidogrel](https://durgical.com/en/pharmacology/clopidogrel/)
- [Ticagrelor](https://durgical.com/en/pharmacology/ticagrelor/)
- [Cangrelor](https://durgical.com/en/pharmacology/cangrelor/)

## Related conditions 2

- [Myocardial Infarction (Heart Attack)](https://durgical.com/en/conditions/myocardial-infarction/)
- [Peripheral artery disease](https://durgical.com/en/conditions/peripheral-artery-disease/)

[← Back to the class: Antiplatelet drugs](https://durgical.com/en/pharmacology/classes/antiplatelet-drugs/)

Educational content on how drugs work; not a prescribing guide and no substitute for a health professional's advice. No doses are given.

Sources: [Vorapaxar: MedlinePlus Drug Information](https://medlineplus.gov/druginfo/meds/a614044.html) (MedlinePlus (U.S. National Library of Medicine), 2025); [3VW7: Crystal structure of human protease-activated receptor 1 (PAR1) bound with antagonist vorapaxar at 2.2 angstrom](https://www.rcsb.org/structure/3VW7) (RCSB Protein Data Bank, 2012).

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Representative model, for educational purposes only.

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Source: https://durgical.com/en/pharmacology/vorapaxar/
License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/pharmacology/vorapaxar/