How does GnRH analogue work?

Gonadotropin releasing hormone agonists (GnRH) are a type of medication that suppresses ovulation by stopping the production of estrogen and progesterone. In order for this axis to function properly and result in ovulation, GnRH has to be released in a pulsatile fashion.

What is a gonadotropin releasing hormone analogue?

GnRH analogues are synthetic drugs similar to natural GnRH. There are two main types: agonists and antagonists. They are used in IVF in order to gain control of the reproductive cycle and to prevent undesired natural secretion of LH and, therefore, ovulation. GnRH analogues are ineffective if taken orally.

What is the difference between GnRH agonist and antagonist?

GnRH agonist acts like GnRH. When GnRH agonist is first given, it causes the pituitary to become more active. However, after a while, the pituitary stops responding to the constant GnRH agonist. By contrast, the GnRH antagonist directly blocks the pituitary from responding to GnRH.

What are the side effects of GnRH?

Common side effects of the GnRH agonists and antagonists include symptoms of hypogonadism such as hot flashes, gynecomastia, fatigue, weight gain, fluid retention, erectile dysfunction and decreased libido. Long term therapy can result in metabolic abnormalities, weight gain, worsening of diabetes and osteoporosis.

Does GnRH cause weight gain?

Suppressing sex hormone levels in premenopausal women with gonadotropin-releasing hormone (GnRH) agonist therapy also causes fat gain. For example, women treated for 16 weeks with a GnRH agonist gained 1.0 kg of fat, which equates to an energy excess of about 80 kcal per day.

What type of hormone is GnRH?

Gonadotrophin-releasing hormone
Gonadotrophin-releasing hormone (GnRH) is produced from cells in the hypothalamus. It is then released into small blood vessels that carry the hormone to the pituitary gland. As a consequence, the pituitary gland produces luteinizing hormone (LH) and follicle-stimulating (FSH) hormones.

What does GnRH mean?

In men, these hormones cause the testicles to make testosterone. In women, they cause the ovaries to make estrogen and progesterone. Also called gonadotropin-releasing hormone, LH-RH, LHRH, and luteinizing hormone-releasing hormone.

How long can you take GnRH?

Currently, GnRH analogues are not licensed for use beyond 6 months. This is because of concerns around thinning of the bones. Under certain circumstances, a Consultant Gynaecologist can sometimes agree to a more prolonged course of treatment (up to 12 months or more).

Does GnRH cause weight loss?

Although some studies have demonstrated weight gain resulted from GnRH agonist therapy,[6,7,11,12] some studies concluded that therapy has no effect on body mass index (BMI). [13,14] Unlike these studies, two studies demonstrated a decrease in BMI with GnRH agonist therapy.

Does GnRH stop menstruation?

In a few women, the recommended dosage does not stop menstruation. If symptoms persist in these women, the dosage may be increased to one spray in both nostrils morning and night. Triptorelin comes as an injection that is injected under the skin or into the buttock muscle once a month or once every three months.

What are GnRH analogs and what are they used for?

GnRH analogs are a type of molecule that has been artificially created by replacing some amino acids within the original GnRH molecule. These new molecules imitate the shape of GnRH and also have a high affinity for its receptors in the pituitary gland. Therefore, GnRH agonists can bind easily to the receptors and prevent the action of natural

Are there any GnRH analogues for prostate cancer?

The GnRH analogues all require parenteral (subcutaneous or intramuscular) administration and are used largely as androgen deprivation therapy for advanced prostate cancer. They are used off-label for precocious puberty, gender dysphoria and infertility.

Are there any GnRH analogues that cause jaundice?

Several of the GnRH analogues have been reported to be associated with transient serum enzyme elevations during therapy, but none have been convincingly implicated in causing clinically significant liver injury with jaundice.

How are GnRH analogues different from histamine antagonists?

Due to the peptide nature of the synthetic analogues oral administration and potential gastrointestinal enzymatic degradation poor bioavailability results necessitating a parenteral delivery system. Some GnRH antagonists have been associated with significant histamine release, inhibiting their widespread use.