Indications
Relugolix is used to treat advanced prostate cancer in men. In some products it is combined with Estradiol and Norethisterone to treat heavy menstrual bleeding caused by uterine fibroids and pain caused by endometriosis in women.
How It Works
Relugolix is a gonadotropin-releasing hormone (GnRH) receptor blocker. It stops the pituitary gland in the brain from sending signals to the testes or ovaries, which quickly lowers testosterone in men and oestrogen in women. Lower testosterone slows the growth of prostate cancer, and lower oestrogen shrinks the symptoms of fibroids and endometriosis.
Dosage and Administration
Take exactly as prescribed by your specialist. It is a tablet taken by mouth once a day, with or without food, at about the same time each day. For prostate cancer treatment usually starts with a higher loading dose on the first day. Do not stop or change the dose without talking to your doctor.
Interactions
- Some medicines such as Rifampicin, Carbamazepine and Phenytoin can lower its effect.
- Medicines such as Erythromycin, Ketoconazole and Ciclosporin can raise its level; if needed, they may be taken at least 6 hours after Relugolix.
- Medicines that prolong the QT interval on the ECG (for example some antiarrhythmics, Haloperidol, Moxifloxacin) need caution.
- Hormonal contraceptives should not be used with the women’s combination product; use non-hormonal contraception.
Contraindications
- Allergy to Relugolix or any ingredient.
- Pregnancy.
- For the women’s combination: history of blood clots, stroke or heart attack, smoking over 35 years of age, liver disease, hormone-sensitive cancers, undiagnosed vaginal bleeding, or osteoporosis.
Side Effects
Common side effects include hot flushes, tiredness, joint or muscle pain, diarrhoea or constipation, headache, sweating and weight gain. Long-term use can reduce bone density. In women, irregular bleeding and changes in mood may occur.
Get urgent medical help if you have chest pain, fainting or a racing or irregular heartbeat, signs of a blood clot (leg swelling or pain, sudden breathlessness), signs of stroke, yellow skin or eyes, severe depression or suicidal thoughts, or a severe allergic reaction.
Pregnancy and Lactation
Relugolix must not be used in pregnancy because it may cause miscarriage. Women should use effective non-hormonal contraception during treatment and for a short time after stopping. It is not recommended while breastfeeding. Men with partners who could become pregnant should follow their doctor’s advice on contraception.
Precautions and Warnings
- Your doctor may check your ECG, blood salts, liver tests and bone density.
- Tell your doctor about any heart rhythm problem, diabetes or depression.
- If you miss a dose, take it within 12 hours; otherwise skip it and take the next dose as usual.
Overdose
There is limited information on overdose. Contact a doctor or hospital straight away; treatment is supportive.
Therapeutic Class
Hormone therapy, oral gonadotropin-releasing hormone (GnRH) receptor antagonist.
Storage
Store below 30°C in a dry place, away from light and out of the reach of children.
Prepared by the Oshud Alo team from standard drug references. For information only; always follow your doctor's advice.