Sixty percent of blood clots happen during a hospital stay or in the 90 days following an admission to hospital.
What is a blood clot?
A blood clot (also called ‘thrombosis’) happens when a clot forms inside your blood vessels (arteries or veins) stopping your blood from flowing normally.
Blood clots are a serious condition and can be life-threatening.
The good news is that half of thrombosis cases are potentially preventable, reducing the risk of death and disability for thousands of people. There are also effective treatments that can deal with blood clots if they are diagnosed quickly.
Signs and symptoms of a blood clot:
- swelling or pain in one leg or arm
- warmth or redness in the leg or arm
- shortness of breath or rapid breathing
- chest pain (particularly when breathing deeply)
- coughing or coughing up blood
- Severe headache that won’t go away
If you have one or more of these symptoms, you may have a blood clot and need urgent treatment
Blood Clot Alert Card
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You have a higher chance of getting a clot in hospital than on an airplane.
What can I do to help myself?
- Ask for your risk of blood clots to be assessed, especially if you are in one of the higher risk groups listed opposite.
- Walk and move as much as possible.
- Drink plenty of fluids.
- If directed to use stockings or medication to prevent or treat a blood clot follow the instructions given to you by your doctor.
- Remember: You are more likely to develop a blood clot if you have been admitted to hospital (and up to 90 days after a hospital stay).
- If you have any signs or symptoms of a blood clot, seek medical treatment urgently.

Am I at risk of developing a blood clot?
You may be at higher risk of developing a blood clot if you:
- have been admitted to hospital and for 90 days after you go home
- have active cancer or are receiving cancer treatment
- are pregnant or have had a baby less than 6 weeks ago
- have become immobile (for example, if you have spent more than 3 days in bed, if you have travelled non-stop for more than 6 hours or if you are currently wearing a leg cast)

Your risk of developing a blood clot may increase if:
- you or a close relative has had a blood clot
- you have had surgery in the last 90 days
- you have thrombophilia (this is a condition that causes your blood to clot more easily)
- you are on the oral contraceptive pill or HRT
- you have heart, lung or inflammatory disease
- you are over 60 years of age
- you are living with overweight or obesity
- you have varicose veins that become red and sore
Do you have a question about blood clots?
Speak to our nurse 01 668 5001 Monday 9am-5pm, Tuesday to Friday 9am-1pm
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Thrombosis support
Our expert nurses can advise and support you with resources and information to help manage your condition.
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