Anticoagulants are a type of anti-clotting medicine used to prevent harmful blood clots in the body. They play an important role in health because blood clots can cause serious conditions like:
- deep vein thrombosis (a blood clot in the veins of the legs)
- pulmonary embolism (a blood clot in the lungs)
- a stroke (a blood clot in a blood vessel in the brain).
Anticoagulants like warfarin are sometimes incorrectly called blood thinners and work by reducing blood clotting. Anticoagulants used to prevent stroke and blood clots include:
- Warfarin (coumadin and marevan)
- Dabigatran (pradaxa)
- Apixaban (eliquis)
- Rivaroxaban (xarelto).
Warfarin
Many people use Warfarin to prevent blood clots. If you take warfarin, it is important that you know how to use it safely and correctly, to avoid side effects, especially bleeding
To help make sure that warfarin is working in your body, you will need regular monitoring blood tests.
Dabigatran (pradaxa)
Dabigatran (pradaxa) is an anticoagulant used to help prevent problems caused by harmful blood clots, such as stroke. Anticoagulants are a type of anti-clotting medicine.
Dabigatran is a medicine taken in a capsule. People can use it for treating:
- atrial fibrillation as an ongoing treatment to prevent stroke as an alternative to warfarin
- hip or knee replacement surgery in order to prevent harmful blood clots. Enoxaparin (clexane) or dalteparin (fragmin) injections (low molecular weight heparins) are the more commonly used alternatives.
Pradaxa is available in capsules. As with other anti-clotting medicines such as anticoagulant and antiplatelet medicines, there is a risk of bleeding as a side effect with dabigatran.
Apixaban (eliquis)
Apixaban (eliquis) can prevent blood clots in veins after a hip or knee replacement surgery.
It can also prevent stroke and blood clots in a condition called atrial fibrillation, which is a type of abnormal heart rhythm.
With atrial fibrillation, part of the heart does not beat the way it should. This can lead to blood clots forming and increase your risk of having a stroke.
It works by inhibiting a blood clot forming substance called Factor Xa. As with other anti-clotting medicines (anticoagulant and antiplatelet medicines), there is a risk of bleeding-related side effects if you are taking apixaban.
Rivaroxaban (xarelto)
Rivaroxaban (xarelto) can help prevent problems caused by harmful blood clots. Rivaroxaban can:
- prevent blood clots in people who've had hip or knee replacement surgery
- prevent stroke in people with atrial fibrillation who have at least one other risk factor for stroke, such as diabetes or hypertension
- treat and prevent deep vein thrombosis (DVT)
- treat and prevent pulmonary embolism (PE).
As with other anti-clotting medicines (anticoagulant and antiplatelet medicines), there is a risk of bleeding-related side effects if you are taking rivaroxaban.
Effects of flying on anticoagulation treatment
The effectiveness of some anticoagulants depends on a stable diet. Variable dietary control during flight can cause problems.
Effects of anticoagulation treatment on operators
The effects of anticoagulation on operators includes:
- overt incapacitation
- distracting pain from gastrointestinal haemorrhage or cerebrovascular bleed
- loss of consciousness from cerebrovascular bleed
- sudden death.
Approach to medical certification
Anticoagulation is an aeromedically significant treatment.
Medical conditions requiring warfarin treatment are serious. Poor control of warfarin can cause a large increase in health risks. This is why it must be very carefully managed.
Pilots and controllers who take anticoagulation are required to ground themselves and notify their Designated Aviation Medical Examiner (DAME) and us.
Permanent multi-crew restriction will be likely if you require anticoagulation long term.
When you start taking warfarin, you need to have a minimum of three international normalised ratio (INR) tests at least one week apart. It must also be within the therapeutic range.
Medicines more likely to gain certification
You are more likely to get certification or be re-certified if you are taking:
- therapeutic warfarin treatment and your condition stabilised within specified INR range
- aspirin.
Medicines less likely to gain certification
You are less likely to gain certification or get re-certified if you are taking:
- clexane: taking clexane is acceptable during initial combination treatment with warfarin but unacceptable for long term treatment
- new anticoagulants: for example, rivaroxaban, dabigatran, ximelagatran and apixaban.
You are unique
Every patient taking anticoagulants is different. We make aeromedical decisions on a case-by-case basis. We base a particular assessment decision on the individual circumstances of the applicant under consideration.
Further information
For further information see NPS Medicine Wise.