Abirakast 500mg Tablet is used to treat:

• Metastatic castration-resistant prostate cancer: Prostate cancer that has spread and keeps growing despite hormone-lowering treatment.

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

• Combination treatment: It is taken with prednisone or prednisolone, and with a GnRH analogue unless you have had surgery to remove the testicles.

• Control, not cure: It slows the growth and spread of prostate cancer and does not cure it.

Abiraterone blocks an enzyme called CYP17, which the body needs to make androgens (male hormones). Lower androgen levels slow the growth of prostate cancer cells.

Blocking this enzyme also causes the body to make more of other hormones that can raise blood pressure and lower potassium. The prednisone or prednisolone taken with it replaces the missing steroid hormones and reduces 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 lower abiraterone levels. Avoid them if possible, or your doctor may adjust the dose.

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

• Diabetes medicines: Using pioglitazone or repaglinide with abiraterone has caused low blood sugar, so sugar levels are monitored.

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

• QT-prolonging medicines: Hormone-lowering treatment can prolong the QT interval, so medicines with the same effect need careful assessment.

• Store Abirakast 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 or crumbled.

• Keep out of the reach of children and pets.

Take Abirakast 500mg Tablet exactly as prescribed. The usual dose is 1000 mg (two 500 mg tablets) once a day, with prednisone 5 mg as directed. Take it on an empty stomach, because food can raise the levels of the medicine in the blood many times over. Swallow the tablets whole with water. Do not crush or chew them.

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

• Do not stop or miss the prednisone or prednisolone unless your doctor advises it.

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

• Women who are pregnant or could become pregnant should wear gloves if they must touch the tablets.

• Blood pressure, potassium and liver function are checked regularly, usually every 2 weeks for the first 3 months and then monthly.

Common side effects of Abirakast 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, muscle 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, especially if prednisone is missed or during an infection.

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

• 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 very stressed.

• Check your blood pressure at home if advised, and report readings that stay high.

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

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

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

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

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

• Report any new swelling, breathlessness, weakness or yellowing of the skin straight away.