What is a commonly used injectable puberty blocker and its typical dose?

Injectable Puberty Blockers: Types and Dosing

The most commonly used injectable puberty blocker is leuprolide acetate (a GnRH agonist), typically administered at doses of 11.25 mg or 30 mg intramuscularly every 3 months for children with precocious puberty, with the higher dose showing better suppression of luteinizing hormone (LH). 1

Types of Injectable Puberty Blockers

• Gonadotropin-releasing hormone (GnRH) analogues are the primary injectable puberty blockers used to suppress testosterone and estradiol production, typically starting in early puberty (Tanner stage 2) 2
• Leuprolide acetate depot is available in multiple formulations, with the 3-month depot formulations (11.25 mg and 30 mg) being commonly used 1
• Triptorelin pamoate is another GnRH agonist available in injectable formulations (3.75 mg, 11.25 mg, and 22.5 mg) administered intramuscularly 3

Dosing Considerations

Leuprolide Acetate Dosing:

• 11.25 mg intramuscularly every 3 months - standard dose, but has shown approximately 78.4% effectiveness in suppressing peak-stimulated LH 1
• 30 mg intramuscularly every 3 months - higher dose with better suppression rates (95.2% effectiveness) 1
• Both doses are administered as intramuscular injections 4

Clinical Efficacy Metrics:

• Successful suppression is defined as peak-stimulated LH <4 IU/L 1, 4
• The 30 mg dose had fewer treatment failures (2 cases) compared to the 11.25 mg dose (9 cases) in clinical studies 1
• Long-term studies (36 months) show maintained LH suppression with both doses 4

Alternative Formulations:

• Triptorelin pamoate is administered as a single intramuscular injection in either buttock 3
• Dosing options include 3.75 mg every 4 weeks, 11.25 mg every 12 weeks, or 22.5 mg every 24 weeks 3

Monitoring and Side Effects

• Regular monitoring of hormonal suppression is essential to ensure efficacy 4
• Common side effects include injection site pain (26.4% of patients), hot flushes, and skeletal pain 3, 4
• Serious potential side effects include:
  • Hypersensitivity reactions including anaphylactic shock and angioedema 3
  • Metabolic changes such as hyperglycemia, diabetes, hyperlipidemia 3
  • Cardiovascular risks including increased risk of myocardial infarction and stroke 3
  • Convulsions have occurred in some patients with or without predisposing factors 3

Duration of Treatment

• Puberty induction typically occurs over a period of 2-3 years 2
• Treatment can be continued until the appropriate time for puberty to begin 2
• For patients with precocious puberty, treatment is typically continued until readiness for normal puberty 4

Special Considerations

• Patients with renal impairment may require more conservative dosing due to reduced clearance 5
• When transitioning off puberty blockers, careful monitoring is needed as pubertal changes will resume 2
• The choice between 11.25 mg and 30 mg doses should be based on the individual's response to treatment, with the 30 mg dose preferred when more complete suppression is required 1, 4