Lutrepulse (Relisorm, Factrel, GnRH, GnRH1)

Introduction

Tradenames: Lutrepulse, Relisorm, Factrel.

Indications

• evaluation of response to gonadotropins
• evaluation of abonormal gonadotropin regulation as in precocious puberty & delayed puberty
• ovulation

Dosage

• women & girls > 12 years of age:
  • 100 ug SC during early follicular phase of menstrual cycle (days 1-7)

Injection: 0.1 mg & 0.5 mg (2 mL)

Adverse effects

• not common (1-10%)
  • pain at site of injection
• uncommon (< 1%)
  • flushing, lightheadedness, headache, rash, nausea, abdominal discomfort

• drug adverse effects of GnRH agonists

Mechanism of action

• GnRH (GnRH1)
• stimulates LH & FSH secretion from the anterior pituitary
• pulsatile secretion* is essential for activity of GnRH
• increased frequency of GnRH pulses occurs during the early follicular phase of the menstrual cycle

* Continuous stimulation with long-acting GnRH agonists (goserelin, gonadorelin) effectively castrates men with prostate cancer.

More general terms

• gonadotropin-releasing hormone agonist (GnRH analog)

Additional terms

• gonadotropin-releasing hormone [GNRH] receptor
• gonadotropin-releasing hormone/factor 1; gonadoliberin 1; LH/FSH-releasing hormone 1; gonadorelin (GnRH1, LHRH-1)