Preventing blood clots during outpatient cancer treatment

A blood clot, also known as venous thromboembolism (VTE), is a blockage that occurs in a deep vein in the body. These blood clots usually happen in a deep vein in the leg and occasionally in other deep veins, such as the arm. This is called deep vein thrombosis (DVT). If a piece of clot breaks off, it can travel through your bloodstream and block a vessel in your lungs. This is called a pulmonary embolism (PE) and rarely, it can be fatal.

If you have a blood clot, you will need urgent treatment. If you notice any of the following symptoms, go to your nearest Emergency Department (A&E) as soon as possible:

People diagnosed with cancer or undergoing major cancer surgery are at an increased risk of developing a blood clot. You can reduce this risk by trying to stay as active as possible during your treatment. You should drink plenty of water as well to avoid dehydration.

Your hospital doctor may also suggest that you take a ‘blood-thinning’ medicine (called an anticoagulant) to help prevent blood clots.

Your doctor may suggest that you start taking a blood-thinning medicine called apixaban around the same time as starting your chemotherapy.

Apixaban is a tablet taken twice a day, about 12 hours apart. For example, you can take it at 8am (in the morning) and 8pm (in the evening). Your doctor will prescribe a low ‘clot prevention’ dose of apixaban and advise you how long you will need to take it. For most people, this is usually while they are on chemotherapy.

If apixaban is not suitable for you, you doctor will offer you a blood-thinning injection called enoxaparin. This is usually self-administered and taken once a day under the skin (subcutaneously). We will show you and/or your carer how to do the injections. We will also give you a ‘sharps bin’ for safe disposal of used syringes. Once full, seal the box, fill in the label on the side and return to UCLH at your next appointment. Do not dispose of syringes in your household waste. Please note that enoxaparin is of animal origin. If you have concerns about using animal products, please speak to your doctor.

Like all medicines, anticoagulants have potential side effects. The most common ones are bleeding and bruising, but most people do not have any issues.

You should contact your GP or go to the nearest Emergency Department (A&E) if you notice any of the following:

• blood in the urine or stools
• severe unexplained bruising
• heavy vaginal bleeding
• bleeding that does not stop by itself
• coughing up blood.

You should also go to the nearest Emergency Department (A&E) if you have had a head injury, even if you don’t lose consciousness. Y

our hospital doctor, and not your GP, will prescribe the apixaban tablets (or enoxaparin injections). You will be able to collect your medication from the Lloyds pharmacy at UCLH. We will let your GP know that you are taking this medication.

Please note:

• You should tell any healthcare professional looking after you (such as a doctor, dentist, nurse or pharmacist) that you are taking a blood thinning medicine. This is because blood thinning medicines may affect some treatments and certain treatments can make blood thinners more or less effective.
• Please tell your GP or hospital team if any other medicines you are taking change. They can then check if this may affect your blood thinner.
• Please do not take herbal medicines or supplements, or anti-inflammatory medicines (such as aspirin, ibuprofen, naproxen or diclofenac) with blood thinning medicines, without first discussing with your doctor, nurse or pharmacist

If you have any general questions about blood-thinning medicines or clot prevention, contact your CNS or cancer pharmacist in the first instance.

My CNS is: ..............................................................................................................................

Tel: ..........................................................................................................................................

Switchboard: 020 3456 7890

NHS website:
nhs.uk/conditions/blood-clots

Cancer Research UK:
cancerresearchuk.org/about-cancer/coping/physically/cancer-and-the-risk-of-blood-clots

University College London Hospitals NHS Foundation Trust cannot accept responsibility for information provided by external organisations.