Abstet 500mg Tablet is used to treat:

• Metastatic castration-resistant prostate cancer: Cancer that has spread and continues to grow despite hormone-lowering treatment.

• Metastatic high-risk castration-sensitive prostate cancer: Cancer that has spread but still responds to hormone treatment.

• Combination treatment: It is taken with prednisone or prednisolone, and with a GnRH analogue unless the testicles have been removed.

• Slowing the disease: It delays the growth and spread of prostate cancer but does not cure it.

Abiraterone blocks the enzyme CYP17, which is needed to make androgens in the testicles, the adrenal glands and the tumour. With less androgen available, prostate cancer cells grow more slowly.

Blocking CYP17 also lets other hormones build up, which can raise blood pressure and lower potassium. The prednisone or prednisolone taken alongside corrects the missing steroid hormones and limits these effects.

Tell your doctor about all prescription medicines, over-the-counter medicines, supplements and herbal products you take.

• Strong CYP3A4 inducers: Rifampicin, phenytoin, carbamazepine, phenobarbital and St John’s wort reduce abiraterone levels. Avoid them if possible, or your doctor will adjust the dose.

• Medicines broken down by CYP2D6: Abiraterone can raise the levels of dextromethorphan, thioridazine and metoprolol.

• Pioglitazone and repaglinide: Using these diabetes medicines with abiraterone has caused low blood sugar, so sugar levels are checked.

• Radium-223: Do not combine with radium-223, because the risk of fractures and death is higher.

• QT-prolonging medicines: Hormone-lowering treatment can prolong the QT interval, so such medicines need careful review.

• Store Abstet 500mg Tablet at room temperature, between 20°C and 25°C.

• Keep the tablets in the original bottle, tightly closed, away from moisture and heat.

• Do not use the tablets after the expiry date.

• Do not use the tablets if they look damaged.

• Keep out of the reach of children and pets.

Take Abstet 500mg Tablet exactly as prescribed. The usual dose is 1000 mg (two 500 mg tablets) once a day, with prednisone as directed. Take it on an empty stomach, because food can greatly increase how much medicine is absorbed. Swallow the tablets whole with water, and do not crush or chew them.

• Do not eat for at least 2 hours before the dose and for at least 1 hour afterwards.

• Do not stop or miss the prednisone or prednisolone unless your doctor tells you to.

• If you miss a dose, take it the next day as usual. Do not take a double dose.

• Pregnant women, or women who could become pregnant, should wear gloves to touch the tablets.

• Blood pressure, potassium and liver function are monitored regularly during treatment.

Common side effects of Abstet 500mg Tablet may include:

• Swelling in the legs or feet

• Low blood potassium

• High blood pressure

• Urinary tract infection

• Diarrhoea

• Hot flushes

• Joint pain

• Tiredness

• Rash

Speak to your doctor if these are severe or do not settle.

Serious side effects

Seek medical attention if you develop:

• Signs of low potassium, such as muscle weakness, twitching or a pounding heartbeat.

• Signs of liver problems, such as yellow skin or eyes, dark urine, nausea, vomiting or abdominal pain.

• Signs of adrenal insufficiency, such as marked weakness, dizziness, nausea or vomiting, particularly if prednisone is missed or you are unwell.

• Chest pain, an irregular heartbeat, breathlessness or sudden swelling and weight gain.

• Bone fractures or severe bone pain.

• A severe allergic reaction, such as swelling of the face, lips or throat.

• Signs of low blood sugar, such as sweating, shakiness or confusion, if you take pioglitazone or repaglinide.

• Take it on an empty stomach, with no food 2 hours before and 1 hour after.

• Never skip the prednisone or prednisolone, and tell your doctor if you are ill or under severe stress.

• Check your blood pressure regularly and report readings that stay high.

• Keep your scheduled blood tests for potassium and liver function.

• Tell your doctor about all medicines, particularly rifampicin, phenytoin, carbamazepine, pioglitazone and repaglinide.

• Ask about bone health. Calcium, vitamin D and exercise may help.

• Use contraception as advised if your partner could become pregnant.

• Wash your hands after handling the tablets, and keep them away from pregnant women.

• Report new swelling, breathlessness, weakness or yellowing of the skin at once.