Megestrol acetate (Megace)

Megestrol acetate is a type of hormone treatment. It is also called Megace or megestrol. It is a man made version of the hormone progesterone. Progesterone is often called a female hormone but men also produce a small amount of it.

Megestrol acetate is a treatment for the following cancers which have come back after treatment or have spread from where they started.

• Breast cancer
• Womb cancer

Megestrol is also a treatment for poor appetite and your doctor may suggest that you take it if you have lost weight because of cancer or its treatment.

Doctors may also suggest it as a treatment for hot flushes in women due to cancer or its treatment.

We don’t fully understand how Megestrol works but think that it 

• Interferes with the hormone balance in the body so that the body makes smaller amounts of the hormones that some cancers depend on to grow
• Interacts with other hormones
• Has a direct effect on the cancer to stop it growing

Megestrol is a tablet. You usually take it once a day but sometimes the dose is divided up so that you take it a couple of times a day. Your doctor will tell you how often and when you should take it.

The side effects associated with Megestrol are listed below.

More than 10 in every 100 people have one or more of these. Remember you may only have one or two of these effects and they may be mild.

• Increase in your appetite – some people take megestrol to help increase their appetite
• Feeling and being sick especially when you first start taking it
• Fluid retention causing ankle and finger swelling
• Weight gain from increased appetite and fluid retention - watching what you eat and exercising regularly can help control your weight
• Megestrol can harm a developing baby – do talk to your doctor about contraception before having treatment if there is any chance you or your partner could become pregnant
• Megestrol may be present in breast milk so it is not advisable for women to breastfeed during treatment or for 2 months after the last dose

Between 1 and 10 in every 100 people have one or more of these.

• Changes in blood sugar levels if you have diabetes – you may have to adjust your dose of tablets or insulin
• High levels of calcium in your blood – you will have regular blood tests to check your calcium levels
• Headache
• Vaginal bleeding in women, which is not part of your period (spotting), or your periods may stop
• Skin rashes, which may be itchy

Fewer than 1 in 100 people have these.

• An allergic reaction
• Blood clots – contact your doctor immediately if you suddenly become breathless or if you have pain, tenderness or swelling in your leg, or your leg feels hot and becomes red
• Hair thinning

The side effects above may be mild or more severe. A side effect may get better or worse through your course of treatment, or more side effects may develop as the course goes on. This depends on

• How many times you've had the drug before
• Your general health
• The amount of the drug you have (the dose)
• Other drugs you are having

Talk to your doctor, pharmacist or nurse about all your side effects so that they can help you manage them.

Tell your doctor about any other medicines you are taking, including vitamins, herbal supplements and other over the counter remedies - some drugs can react together.