Fulvestrant is a hormonal therapy used to control breast cancer that has spread to other parts of the body (secondary breast cancer). It is used to help control the cancer and its symptoms. Fulvestrant may be prescribed as a single agent or in combination with other anticancer therapies.
Your clinical team will be happy to answer any questions you have about your treatment.
Hormones are substances produced naturally in the body. They act as chemical messengers and help control the activity of cells and organs. Hormonal therapies are drugs that interfere with the way hormones are made or how they work in the body. Many breast cancers rely on the hormone oestrogen to grow. This type of breast cancer is called oestrogen receptor-positive (ER positive) breast cancer.
Fulvestrant works by binding to the oestrogen receptors to stop them working. This slows down or stops the cancer cells from growing. Fulvestrant also reduces the number of oestrogen receptors on the breast cancer cells.
Fulvestrant may be used in women who have gone through the menopsause. It may also be used in men, patients who were assigned male at birth, or in patients who have not gone through the menopause. In this case, fulvestrant will usually be combined with goserelin or leuprorelin injections.
Your treatment
Fulvestrant is administered as an injection into the muscle (intramuscular) in the buttocks.
Fulvestrant is given as 2 injections, 1 into each buttock. The injections take 1 to 2 minutes each.
It is given as a 500mg dose every 2 weeks for the first 3 doses. After this, it is given every 4 weeks.
This treatment can have serious or possibly life-threatening side effects. It is very important that you report side effects straight away. Don’t delay, if you feel unwell, please ring The Christie Hotline on 0161 446 3658. The lines are open 24 hours a day.
If you feel unwell, you have symptoms of an infection or your temperature is 37.5ºC or above, or below 36ºC contact The Christie Hotline straight away.
Possible side effects
Hormone therapy can cause different side effects. Some are more likely to occur than others. Everyone is different and not everyone gets all the side effects. Most side effects are usually temporary, but in some rare cases they can be life-threatening. It is important to tell your clinical team about any side effects so they can be monitored and, where possible, treated.
Common side effects (more than 1 in 10)
Injection site reactions
Fulvestrant may cause temporary pain and inflammation may occur around the injection site. This will usually last 1 to 2 days. Inform your clinical team if you experience this.
If you are taking an anticoagulant there may be increased risk of bruising and bleeding around the injection site. Please inform your clinical team if you are taking any anticoagulant medications.
Hot flushes
Hot flushes and sweats may occur but lessen after the first few months. Cutting down on nicotine, alcohol and hot drinks containing caffeine, such as tea and coffee, can help. Dress in layers, so you can remove clothes as needed. Natural fabrics, such as cotton, may feel more comfortable. If hot flushes are a problem, tell your clinical team. Low doses of certain antidepressant drugs can help to reduce flushes.
Joint and muscle pain
You may have pain and stiffness in your joints, and sometimes in your muscles or back, while taking fulvestrant. Let your clinical team know if this happens. They can prescribe painkillers and give you advice. Being physically active and maintaining a healthy weight can help reduce joint pain and keep them flexible.
Fatigue (feeling tired)
You may feel tired, sleepy or feel you have no energy when you start taking fulvestrant. Try to pace yourself until this improves. It’s important to get the right balance of having enough rest and being physically active. Regular short walks will help you to feel less tired. If you feel sleepy, don’t drive or operate machinery.
Sickness and diarrhoea
Any sickness or nausea is usually mild, but let your clinical team know if this happens. Fulvestrant may also cause indigestion or tummy pain. Let them know if you have any of these symptoms. They can prescribe drugs to help.
If diarrhoea becomes a problem during or after your treatment, anti-diarrhoea tablets can be prescribed by your clinical team. Ask the staff for a copy of The Christie booklet ‘Eating – help yourself’ which has some useful ideas about diet when you are having treatment.
Appetite and weight gain
If you don’t have much appetite, try eating small, frequent meals or snacks. If problems with eating don’t get better, talk to your clinical team.
Headache and dizziness
If you have headaches, let your clinical team know. They can usually be controlled with painkillers you can buy yourself. Fulvestrant may also cause dizziness. Let your clinical team know if this is a problem.
Skin rash and dry skin
You may get a mild skin rash or dry skin. Tell your clinical team if this happens. It’s very important to contact your clinical team straight away if you get a severe skin rash.
Hair thinning
Your hair may become, drier and more brittle while taking fulvestrant. Your hair will return back to normal after treatment finishes.
Vaginal bleeding and dryness
For some patients, fulvestrant causes vaginal bleeding. If this happens it is most likely in the first few weeks of treatment, or when you change from another hormonal therapy to fulvestrant. If bleeding continues for more than a few days, tell your clinical team.
For some patients, fulvestrant causes vaginal dryness. Non-hormonal creams and gels or lubricants can help reduce dryness and discomfort during sex. You can buy these at a chemist or your clinical team can prescribe them. Although breast cancer is less common in men and patients that do not produce this hormone, this treatment can affect male hormones. This may lead to changes in sex drive and sexual function including erectile dysfunction. Talk to your GP for advice if these become an issue.
Liver changes
Fulvestrant can sometimes cause changes in the way your liver works. Your clinical team will arrange for you to have regular blood tests to check your liver is working properly. You are very unlikely to notice any problems.
Pain, numbness and tingling in hands and fingers
These symptoms may be due to carpal tunnel syndrome, which is caused by pressure on a nerve in the wrist. It is more common in people taking fulvestrant. Tell your clinical team if you have these symptoms.
Constipation
You may become constipated. Try to drink plenty of fluids and eat foods high in fibre. Tell your clinical team who may prescribe a suitable laxative. Please contact The Christie Hotline if your constipation lasts more than 3 days or you experience abdominal discomfort.
Uncommon side effects (less than 1 in 10)
Allergic reaction
Sometimes fulvestrant can cause an allergic reaction. Signs of a reaction can include a rash, feeling itchy, wheezing, shortness of breath, swelling of your face or lips or feeling unwell.
Tell your clinical team straight away if you have any of these symptoms. If you develop any of these symptoms after you get home, contact The Christie Hotline on 0161 446 3658 straight away or go to the nearest A&E department.
Urinary infection
Let your clinical team know if you have pain or discomfort when you pass urine, if you need to go more often, or your urine is cloudy or smelly. Drink lots of fluids if you think you may have an infection.
Blood clots
People with cancer are at a higher risk of developing bloods clots. The medical name for this is a thromboembolism or a deep vein thrombosis (DVT). The most common places to develop a blood clot are in the leg or the lungs. You must contact The Christie Hotline on 0161 446 3658 immediately of you experience any of the following:
pain, redness and swelling of your arm or leg(s). The area may feel warm to touch.
breathlessness, pain in your upper back, light-headedness, coughing up blood. For any chest pain, please call 999 immediately.
You can help to prevent a clot by taking regular short walks to keep the blood moving, do simple exercises such as bending and straightening your toes every hour if you are unable to move around much and drink plenty of fluids. Most clots can be treated successfully using drugs to help thin the blood (anticoagulants).
Bruising and bleeding
Fulvestrant can sometimes reduce the production of platelets which help the blood clot. Let your clinical team know if you have any unexplained bruising or bleeding, such as nosebleeds, bloodspots or rashes on the skin, and bleeding gums.
Nerve damage
Fulvestrant may cause injection site related nerve damage. Contact your clinical team if you develop any of the following symptoms in your legs following a fulvestrant injection; numbness, tingling or weakness, burning pain or sciatica.
Sex, contraception and fertility
Fulvestrant is usually used when you have been through the menopause. However, if you have recently been though the menopause, had a chemotherapy-induced menopause or are having treatment to stop your ovaries working, there is still a small chance that you could become pregnant. It is important not to get pregnant while having this treatment as this drug may harm a developing baby. If you are sexually active you must use effective contraception whilst taking fuvestrant.
Flu vaccinations
We advise that all patients receive a flu vaccination when this is offered. However, if you’re thinking of having any other vaccinations, do check with your Christie doctor first, because some vaccines should be avoided.
COVID-19 vaccinations
We advise that all patients receive a COVID-19 vaccination when this is offered.
Other medicines
Some medicines and herbal remedies may interact with fulvestrant. Please consult your doctor or pharmacist if you are starting any new medications. Some medicines and herbal remedies may interact with fulvestrant. Please consult your doctor or pharmacist if you are starting any new medications.
Contacts
If you have any general questions or concerns about your treatment, please contact your consultant’s secretary or breast cancer nurse.
For urgent advice, ring The Christie Hotline on 0161 446 3658 (24 hours a day, 7 days a week).