Gonadotropin releasing hormone agonists for PMS
Treatment for severe premenstrual syndromes (PMS) or premenstrual dysphoric disorder (PMDD)
Gonadotropin Releasing Hormone Agonists (GnRH) are licensed for the short-term treatment for uterine fibroids or endometriosis. GnRH agonists may be used outside of the licensed indication to treat severe cyclical hormonal symptoms. Their use is endorsed by the Royal College of Obstetricians and Gynaecologists (RCOG) and the National Association for Premenstrual Syndromes (NAPS) through their respective guidelines.
GnRH agonists act on the pituitary gland in the brain to suppress ovulation and production of ovarian hormones, inducing a reversible chemical menopause. As PMS or PMDD symptoms are related to the menstrual cycle these symptoms will then resolve. GnRH agonist may be used to confirm the diagnosis of PMS/PMDD or used as a long-term treatment with hormone replacement.
Risks of long-term GnRH agonists
The licenced use of GnRH agonist is limited to six months due to the risk of osteoporosis. When used for PMS/PMDD either combined hormonal contraception (CHC) or combined hormone replacement therapy (HRT) will be prescribed at the same time. To ensure no harm is done whilst on treatment, a base-line bone mineral density scan (BMD/DEXA) is necessary before treatment is started and repeated every 12-18 months.
Prescriptions
GnRH agonists are generally prescribed by your general practitioner (GP) with ongoing supervision from your specialist team. Where this is not possible, the hospital may continue prescribing responsibility and further prescriptions should be requested via the menopause page on the Trust web site.
Contraindications to GnRH agonists
- You are pregnant or trying to become pregnant within the next 12 months (except where GnRHa is used as part of fertility treatment).
- You have previously had an allergic reaction to this type of medicine.
- You are breastfeeding.
Even when your periods have stopped there is a small increased pregnancy risk. Please discuss contraceptive needs with your health care practitioner.
Hormone add-back
GnRH agonists action is to supress ovarian function and may cause common side-effects due to estrogen deficiency. Commonly these may include hot flushes, reduced sex drive, headaches, mood changes including depression, vaginal dryness and breast symptoms. Hormone replacement alleviates these symptoms and the dose may need adjusting if they are persistent. Please speak to your GP or specialist.
Discontinuing treatment
Please discuss with your GP or specialist if you wish to discontinue treatment. Your hormone replacement should be discontinued until your naturel periods have returned and contraception continued if required.