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Cetrorelix

Hormone Regulation & Endocrine Support

Cetrorelix is a synthetic GnRH antagonist used to suppress LH and FSH secretion during controlled ovarian stimulation in IVF. It enables precise timing of ovulation and prevents premature hormonal surges that can compromise reproductive outcomes.

Reconstitute
1 mL BAC + 0.25mg vial
3 mcg/unit
Daily Range
0.25–0.5 mg Subcutaneous (SQ)
Once daily during ovarian stimulation (days 5–10 of cycle)
Standard Dose
0.25 mg
Cycle
4–8 weeks
then reassess
CetrorelixGnRH antagonistfertility treatmentLH suppressionIVF protocol

Dosing & Reconstitution Guide

Clinical studies often use 0.25–3 mg/day subcutaneously. Use is limited to regulated fertility and endocrine protocols.

Standard / Gradual Approach

0.25mg Vialdaily
PhaseDoseVolume
Days 5–6 onward0.25 mg dailyFull 0.25 mg vial SQ
Until trigger day0.25 mg dailyContinue daily until hCG trigger

Standard / Gradual Approach

3mg Vialsingle-dose
PhaseDoseVolume
Stimulation day 73 mg onceFull 3 mg vial SQ (lasts ~4 days)

Protocol Summary

Subcutaneous (SQ): Once daily during ovarian stimulation (days 5–10 of cycle) · Dose range 0.250.5 mg with gradual titration
Cycle Length: 4–8 weeks typical; reassess before extending

Frequency & Cycling

SubQ Injection

Inject 0.25 mg daily during ovarian stimulation (typically days 5–10 of cycle). Used in ART protocols under strict monitoring.

🧪 Quick Start

Vial Size
25 mg
BAC Water
1 mL
Concentration
25000 mcg/unit

Potential Benefits & Use Cases

Cetrorelix is a prescription fertility drug not approved for any use beyond regulated clinical settings.
Suppresses gonadotropin secretion in fertility-related research
Prevents premature ovulation in IVF clinical protocols
Studied for HPTA suppression in hormone regulation studies
Investigated for prostate health in androgen-dependent models
Provides precise control over reproductive hormone cycles
Clinical data Strong preclinical Limited data

Mechanism of Action

Antagonizes GnRH receptors in the pituitary gland
Suppresses secretion of LH and FSH from the anterior pituitary
Prevents premature LH surge and ovulation during ovarian stimulation
Supports controlled follicle development for IVF or ICSI procedures

Lifestyle & Optimization

timing

Used exclusively in IVF/fertility protocols under reproductive endocrinologist supervision.

diet

Adequate hydration supports ovarian function. Avoid alcohol and limit caffeine during stimulation cycles.

exercise

Reduce strenuous exercise during ovarian stimulation to minimize ovarian torsion risk.

sleep

Adequate rest during stimulation cycles.

Side Effects & Safety

Common Side Effects

Mild injection site reaction
Headache
Abdominal discomfort

Contraindications & Warnings

May impair fertility if not properly dosed
Should be used under medical supervision during ART cycles

Long-Term Safety Data

Long-term hormone suppression risks unknown; short-term ART use well tolerated

🧮 Dose Calculator

Concentration
2.5
mcg/unit
Draw Volume
200
units (2.000 mL)
For a 500 mcg dose, draw 200 units on a U-100 insulin syringe
🧬

Bioavailability & Absorption

SubQ Injection
High absorption with peak plasma concentration within 1–2 hours
Oral Administration
Ineffective orally due to enzymatic degradation
Half-Life
5–20 hours depending on dose and formulation
Degradation
Slow renal and hepatic peptide clearance
Tissue Specificity
Primarily acts on anterior pituitary GnRH receptors
⚗️

Peptide Details

Molecular Weight
1431.4
Formula
C70H92ClN17O14
Sequence
Ac-D-Nal-D-Phe-D-His-D-Trp-D-(2-Pal)-D-Tyr-D-Ser-OH
⚖️

Legal Status & Regulatory

RegionStatus
FDAApproved
EUApproved
AustraliaApproved
CanadaApproved

Storage Instructions

Lyophilized (Powder)
Store at 2–8°C (refrigerate). Protect from light. Stable until expiration date.
Reconstituted (Mixed)
Use immediately after reconstitution. Do not store.