Hot flushes and sweats
These are common. During a flush, your neck and face may feel warm and look red. Flushes can last for a few seconds or for up to 10 minutes. You may have sweats then feel cold and clammy. Some people feel anxious or irritable during a hot flush.
There are things you can do to try to reduce flushes:
- Wear clothes made from natural fabrics, such as cotton.
- Dress in layers of clothes that you can remove as needed.
- Use cotton sheets and have layers of bedding.
- Keep the room temperature cool or use a fan.
- Have cold drinks rather than hot ones. Try to avoid drinks with caffeine in them.
You may have fewer hot flushes and sweats as your body adjusts to hormonal treatment. Or your doctor can prescribe drugs to help. Some people continue to have flushes and sweats, but they usually stop a few months after treatment finishes.
Women coping with hot flushes can read more in our information about managing menopausal symptoms.
Bone thinning (osteoporosis)
Taking this treatment for several months or more can cause bone thinning. This is called osteoporosis. This can increase your risk of a broken bone (fracture). You may have bone density scans to check your bone health before and during treatment.
Keeping physically active and eating a healthy diet helps look after your bones. Your doctor may prescribe drugs called bisphosphonates to help protect your bones. They may also advise you to take calcium and vitamin D supplements.
Tiredness
Feeling tired is a common side effect. Try to pace yourself and plan your day so you have time to rest. Gentle exercise, like short walks, can give you more energy. If you feel sleepy, do not drive or operate machinery.
Muscle or joint pain
You may get pain in your muscles or joints. If this happens, tell your doctor so they can give you painkillers. Being physically active and keeping to a healthy weight may help with the pain. It will also keep your joints flexible. Let your doctor or nurse know if it does not get better.
Feeling sick
Any sickness is usually mild. But let your doctor or nurse know if this happens. Try taking your letrozole tablets with food or at night.
Indigestion or tummy pain
Letrozole may also cause indigestion or tummy pain. Let your doctor or nurse know if you have any of these symptoms. They can prescribe drugs to help.
Loss of appetite
Try to eat small, frequent meals or snacks instead of 3 meals a day. This may be helpful if you have lost your appetite or find it difficult to eat big meals.
Hair thinning
Your hair may become thinner while taking this treatment. This is usually mild. Ask your nurse for advice if this is a problem for you.
Skin changes
This treatment may affect your skin. Your doctor or nurse can tell you what to expect. If your skin feels dry, try using an unperfumed moisturising cream every day. The treatment may cause a rash, which may be itchy.
Always tell your doctor or nurse about any skin changes. They can give you advice and may give you creams or medicines to help. Any changes to your skin are usually temporary and improve when treatment finishes.
Mood and behaviour changes
Some people find they have a low mood while taking letrozole. Or you may have problems concentrating, feel anxious or have difficulty sleeping. Talk to your nurse or doctor if you have these changes so they can give you support and advice.
Headaches
This treatment may cause headaches. If this happens, tell your doctor or nurse. They can give you painkillers.
Feeling dizzy
Letrozole may cause dizziness. Let your doctor or nurse know if this is a problem.
Weight gain
You may put on weight when you are having this treatment. Eating healthily and being active can help you keep to a healthy weight. Your doctor, nurse or dietitian can give you more advice.
Vaginal bleeding or dryness
This treatment can cause vaginal bleeding or dryness. Bleeding may happen when you start taking anastrozole or change to it from another treatment. If bleeding continues for more than a few days, tell your doctor or nurse.
You can use non-hormonal creams, gels or lubricants to help with vaginal dryness and any discomfort during sex. You can buy these from a chemist, or your doctor can prescribe them.
Raised blood pressure
Tell your doctor or nurse if you have ever had any problems with your blood pressure. Your nurse will check it regularly during your treatment.
Raised cholesterol level
This treatment can raise the level of cholesterol (a fatty substance) in the blood. Your doctor may check this with a blood test. Your doctor may give you medicines to control your cholesterol levels.
Build-up of fluid
You may get swollen feet and ankles because of fluid building up. If you notice this or any other swelling, let your doctor know.