Gonadorelin (GnRH) dosing & administration
The master hormone that controls your reproductive system and fertility
Written by Michael Carroll — Owner, Director of Research · Reviewed by the Peptide Initiative Research Team · Editorial standards
Dosing
How much do I take?
Subcutaneous: A small injection into the fatty layer just under the skin — the same way insulin is given.
Bioavailability High — most of the dose reaches your bloodstream, just more gradually than an IV.
100 mcg
Frequency
Single dose
Duration
One-time diagnostic test
FDA-labeled gonadotropin (LH/FSH) stimulation test for pituitary reserve; 100 mcg given once subcutaneously (or IV), with LH measured at 0, 15, 30, 45, 60 and 120 minutes (Factrel) [4].
Timing
Best time to take
Administer Gonadorelin (GnRH) 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?
Gonadorelin (GnRH) 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
Gonadorelin (GnRH) 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
Administration
How do I use it?
Reconstitution
What you need
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
Storage
Before reconstitution
Store Gonadorelin (GnRH) in the refrigerator at 36-46°F (2-8°C) in its original packaging. Protect from light and moisture. Do not freeze. Check the expiration date before use. Some formulations may be stored at room temperature for limited periods—check your specific product labeling.
After reconstitution
Once reconstituted, Gonadorelin (GnRH) should be kept refrigerated at 36-46°F (2-8°C) and used within the timeframe specified on your product labeling (typically 14-28 days). Label the vial with the reconstitution date. Do not use if the solution appears cloudy, discolored, or contains particles.
Signs of degradation — discard the vial
Sample daily schedule
As prescribed (once daily)
As prescribed by your healthcare provider injection
Site: Subcutaneous injection—rotate sites if applicable
Maintain a consistent schedule for optimal results with Gonadorelin (GnRH). Set reminders if needed. If you miss a dose, follow your healthcare provider's instructions—do not double up on doses to compensate.
Safety
Is it safe?
Side effects
Commonly reported: Mild headache, Local injection site reactions (redness, swelling), Temporary hot flashes, Mood changes or emotional sensitivity, Nausea or mild stomach upset, Allergic skin reactions, Dizziness or lightheadedness, Temporary changes in vision, Joint or muscle aches, Insomnia or sleep disturbances, Severe allergic reactions (difficulty breathing, swelling), Severe hormonal imbalance symptoms, Ovarian hyperstimulation syndrome (OHSS), Signs of blood clots (chest pain, leg swelling), Severe mood changes or depression
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 Gonadorelin (GnRH)
- Pregnancy or planning to become pregnant (unless specifically approved for use during pregnancy)
- Abnormal lab results or clinical markers that suggest adverse effects
Gonadorelin (GnRH) 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.
Flagged pairings
- GnRH Antagonists — These directly block GnRH action, making them counterproductive when used together
- Dopamine Agonists — Can suppress GnRH release and interfere with its reproductive effects
- Long-acting GnRH Agonists — Initial flare can interfere with gonadorelin's pulsatile signaling mechanism
Published research
What the studies show
Bandai K, et al. · 2026
GnRH effectively synchronized ovulation in cattle when combined with progesterone protocols. Extended treatment protocols improved fertility outcomes in Japanese Black cows used in breeding programs.
Research investigators · 2026
GnRH antagonists improved quality of life and symptom severity without significant fibroid volume reduction compared to placebo. When combined with other medications, GnRH therapy effectively managed fibroid-related symptoms in women.
Couldwell M, et al. · 2025
GLP-1 agonists demonstrated effects on the GnRH system and reproductive outcomes, including improvements in fertility in obese patients. The review highlighted the complex interactions between metabolic and reproductive hormone axes.
Wyeth (Factrel, gonadorelin hydrochloride) - prescribing information · 1982
Human Factrel (gonadorelin HCl) is indicated for evaluating the functional capacity and response of the gonadotropes of the anterior pituitary. The diagnostic dose is 100 mcg given as a single subcutaneous or intravenous injection, with serum LH measured at baseline and at 15, 30, 45, 60 and 120 minutes to assess pituitary gonadotropin reserve.
Santoro N · 1990
Pulsatile gonadorelin acetate 5 mcg every 90 minutes (range 1-20 mcg) by intravenous pump induced ovulation in hypothalamic amenorrhea; intravenous delivery outperformed subcutaneous.
Head to head
Gonadorelin (GnRH) compared
Want the full picture?
The complete Gonadorelin (GnRH) research profile: mechanism of action, clinical studies, effectiveness timeline, and FAQ.