Hormone Support Protocol
CetrorelixComplete Dosing & Administration Guide
Fast-acting GnRH antagonist that stops premature ovulation during IVF cycles
Dose Range
0.25 mg-3 mgmg
Frequency
Once daily
Route
Subcutaneous injection
Cycle Length
Ongoing/indefinite
Dosing
How much
do I take?
Timing
Best time to take
Administer Cetrorelix at the same time each day (or on the same day each week for weekly injections). Many users prefer morning or evening administration. Pick a time you'll remember consistently.
With food?
Cetrorelix injections can be given regardless of meal timing. However, if GI effects occur, administering on an empty stomach or with a light meal may help reduce discomfort.
If stacking
Cetrorelix should be used as directed by your healthcare provider. If combining with other medications or supplements, discuss potential interactions with your provider. Avoid combining with compounds that have overlapping mechanisms unless specifically guided by a medical professional.
Adjusting Your Dose
Increase if
- +You've tolerated the current dose for the recommended period without significant side effects
- +Therapeutic goals haven't been met at the current dose level
- +Your healthcare provider recommends dose escalation based on your response
- +Lab work or clinical assessments support a higher dose
Decrease if
- -Side effects are bothersome or impacting daily life despite management strategies
- -You experience any signs of an adverse reaction
- -Lab results indicate the need for dose reduction
- -Your healthcare provider recommends a lower dose based on your response
Signs of right dose
- ✓Therapeutic goals being met with minimal side effects
- ✓Stable and consistent response to treatment
- ✓Lab values or clinical markers trending in the right direction
- ✓Good tolerance with manageable or absent side effects
Dosing Calculator
Calculate Your Exact Dose
Step 1: Peptide Weight
Find the weight printed on your peptide vial label
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The peptide weight is printed on the label
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The weight is on the label
Administration
How do I
use it?
Reconstitution
What you need
- •Cetrorelix vial (lyophilized powder or solution)
- •Bacteriostatic water or sterile sodium chloride for reconstitution
- •Alcohol swabs for cleaning vial tops and injection sites
- •Appropriately sized syringes with fine-gauge needles (27-30 gauge)
- •Sharps disposal container
Injection
Route
Subcutaneous injection (into the fatty tissue just under the skin)—allows for consistent absorption and can be self-administered at home after proper training
Best sites
- •Abdomen (stomach area)—at least 2 inches from the belly button, most popular choice for self-injection
- •Front of thighs—middle to upper portion of the outer leg
- •Back of upper arm—outer area (may need assistance from another person)
Technique
- 1.Wash your hands thoroughly with soap and water before handling supplies
- 2.Clean the injection site with an alcohol swab and let it air dry completely
- 3.Pinch a fold of skin at the chosen injection site
- 4.Insert the needle at a 45-90 degree angle (depending on needle length and body composition)
- 5.Inject the medication slowly and steadily over 5-10 seconds
- 6.Release the skin fold and remove the needle, applying gentle pressure with a clean swab
- 7.Rotate injection sites to prevent tissue irritation or lipodystrophy
- 8.Dispose of the needle safely in a sharps container—never recap or reuse needles
Storage
Signs of degradation
Sample Daily Schedule
Safety
Is it
safe?
Safety Profile
Cetrorelix is an FDA-approved GnRH antagonist used exclusively in assisted reproductive technology with proven safety in short-term reproductive cycles. Unlike GnRH agonists, cetrorelix lacks the initial testosterone flare, making it well-tolerated for ovarian stimulation. Primary side effects are mild and local—injection site reactions (erythema, bruising) occur in 10-20% of patients. No systemic bone loss, cardiovascular complications, or serious adverse events have been reported in the reproductive context where treatment duration is limited (typically 7-10 days). The short treatment window in IVF protocols minimizes long-term safety concerns. Hypersensitivity reactions are rare but possible.
Cetrorelix was studied through Phase 3 clinical trials specifically for IVF applications, with large multicenter randomized trials demonstrating safety and efficacy. Regulatory approval in the U.S. and Europe was based on comprehensive Phase 2 and Phase 3 data in infertile patients undergoing controlled ovarian hyperstimulation. Long-term safety data beyond the typical 1-2 week treatment cycle is limited because the drug is not used for chronic applications.
Common Side Effects
Experienced by some users
Injection site reactions (redness, itching, swelling)
Injection site reactions (redness, itching, swelling)
Management: Consult your healthcare provider for guidance.
Headache
Headache
Management: Consult your healthcare provider for guidance.
Nausea
Nausea
Management: Consult your healthcare provider for guidance.
Mild abdominal discomfort
Mild abdominal discomfort
Management: Consult your healthcare provider for guidance.
Dizziness
Dizziness
Management: Consult your healthcare provider for guidance.
Allergic reactions (rash, difficulty breathing)
Allergic reactions (rash, difficulty breathing)
Management: Consult your healthcare provider for guidance.
Ovarian hyperstimulation syndrome (OHSS) if used with other fertility drugs
Ovarian hyperstimulation syndrome (OHSS) if used with other fertility drugs
Management: Consult your healthcare provider for guidance.
Ovarian cysts
Ovarian cysts
Management: Consult your healthcare provider for guidance.
Vaginal bleeding
Vaginal bleeding
Management: Consult your healthcare provider for guidance.
Mood changes
Mood changes
Management: Consult your healthcare provider for guidance.
Liver enzyme changes
Liver enzyme changes
Management: Consult your healthcare provider for guidance.
Pelvic pain
Pelvic pain
Management: Consult your healthcare provider for guidance.
Severe allergic reaction
Severe allergic reaction
Management: Consult your healthcare provider for guidance.
Stop and Seek Help If
- ×Severe or worsening side effects that don't improve with dose adjustment or supportive care
- ×Signs of an allergic reaction—rash, hives, swelling, or difficulty breathing
- ×Your healthcare provider recommends discontinuation based on your clinical response
- ×Development of any new medical condition that may be contraindicated with Cetrorelix
- ×Pregnancy or planning to become pregnant (unless specifically approved for use during pregnancy)
- ×Abnormal lab results or clinical markers that suggest adverse effects
Cetrorelix should only be started, adjusted, or discontinued under medical supervision. This information is for educational purposes only and does not replace professional medical advice. Never stop a prescribed treatment without consulting your healthcare provider first, as abrupt discontinuation may have consequences.
Interactions
With other peptides
- ✓FSH stimulates your ovaries to grow multiple follicles while cetrorelix prevents premature ovulation—they work together perfectly.
- ✓This combination hormone provides both FSH and LH stimulation while cetrorelix blocks the unwanted LH surge.
- ✓After egg retrieval, progesterone prepares your uterus for implantation while cetrorelix has done its job preventing ovulation.
With medications
- !GnRH Agonists (Lupron, Buserelin) - Both affect GnRH signaling. Using both together would be like fighting yourself—they work against each other.
- !Certain hormone contraceptives - Birth control pills taken right before cetrorelix can interfere with how well the antagonist works. Your doctor will tell you when to stop birth control.
With supplements
- ✓Multivitamins - Generally safe to take alongside Cetrorelix. Space doses apart if taking oral formulations to ensure optimal absorption.
- ✓Electrolyte supplements - Helpful if experiencing any GI side effects that could lead to dehydration. Safe to combine.
Want the Full Picture?
View the complete Cetrorelix research profile including mechanism of action, clinical studies, effectiveness timeline, and FAQ.
View Full Cetrorelix Profile