How to Reconstitute Sermorelin: Dosing Math (mg, mL, IU, Units)

Disambiguation: what Sermorelin is and is not

Sermorelin is a GHRH(1-29) analogue, not human growth hormone (HGH) itself and not a GH secretagogue peptide like ipamorelin or CJC-1295. It works by stimulating the pituitary to release the body's own growth hormone, rather than supplying growth hormone directly. A branded version, Geref, previously held FDA approval for diagnostic and pediatric growth-hormone-deficiency use before being withdrawn from the US market for commercial reasons in 2008. Sermorelin sold today comes from 503A or 503B compounding pharmacies, meaning it is a compounded preparation, not an FDA-approved drug product, and its use in adults for anti-aging, sleep, or body-composition goals is off-label relative to the original pediatric indication and has never had an on-market FDA-approved adult formulation.

The core reconstitution formula

Concentration (mg/mL) = amount of peptide in the vial (mg) ÷ volume of bacteriostatic water added (mL)

Every downstream calculation, including how many units to draw on an insulin syringe, comes from this ratio. Get this number right before drawing a first dose.

Choosing a target concentration

The two concentrations most commonly used in compounding-pharmacy protocols are 1 mg/mL and 2 mg/mL. A 1 mg/mL solution keeps typical dose volumes between roughly 0.10 and 0.50 mL, which is easier to read accurately on a standard U-100 insulin syringe than the smaller volumes a 2 mg/mL solution would require.

Whatever concentration you land on, write it on the vial label. Never rely on memory once more than one vial is in the refrigerator.

Converting micrograms to milliliters

Prescriptions are frequently written in micrograms (mcg). One milligram equals 1,000 micrograms.

At 1 mg/mL:

• 200 mcg = 0.20 mL = 20 units on a U-100 syringe
• 300 mcg = 0.30 mL = 30 units
• 500 mcg = 0.50 mL = 50 units

At 2 mg/mL:

• 200 mcg = 0.10 mL = 10 units
• 300 mcg = 0.15 mL = 15 units
• 500 mcg = 0.25 mL = 25 units

Why "IU" does not apply to Sermorelin

International Units (IU) describe biological activity and are used for drugs standardized that way, such as insulin or hCG. Sermorelin doses are expressed in milligrams or micrograms by weight, not IU. When a prescription or pharmacy label says "20 units," it means 20 graduation marks on a U-100 insulin syringe (0.20 mL), not 20 IU. Confirm the syringe barrel is printed "U-100" before drawing; a U-40 syringe (used in some veterinary and international settings) has only 40 marks per mL and will deliver a different volume for the same "unit" number.

Which diluent should you use, and why does it matter?

Bacteriostatic water for injection (BAC water) contains 0.9% benzyl alcohol as a preservative, which is why it is the standard diluent for multi-dose peptide vials that will be used repeatedly over several weeks. Preservative-free sterile water for injection is intended for single-dose use; using it for a vial you plan to draw from over weeks raises microbial contamination risk once the stopper has been punctured multiple times.

Older clinical reports flagged benzyl alcohol toxicity risk specifically in neonates receiving large-volume intravenous flush solutions in intensive-care settings. That alert does not describe adult subcutaneous peptide injections, where the benzyl alcohol dose per injection is a small fraction of the exposures studied in neonatal ICU cases. This distinction is worth understanding rather than assuming the neonatal warning transfers directly to an adult self-injection context.

General FDA guidance on sterile drug manufacturing describes preservative use and aseptic technique for injectable products (FDA, sterile drug products guidance); it is written for manufacturers, not patients, but it is the closest primary regulatory source behind why preserved diluents are handled the way compounding pharmacies instruct.

Step-by-step reconstitution technique

1. Wash hands for 20 seconds with soap and water.
2. Swab the rubber stoppers of both the BAC water vial and the Sermorelin vial with an alcohol swab and let them air-dry for about 30 seconds.
3. Draw the calculated volume of BAC water into a syringe (for example, 2.0 mL for a 2 mg vial targeting 1 mg/mL).
4. Insert the needle into the Sermorelin vial at an angle and let the water run down the inside glass wall rather than directly onto the powder.
5. Depress the plunger slowly. Running the diluent down the wall reduces foaming and mechanical stress on the peptide.
6. Do not shake the vial. Roll it gently between your palms until the powder fully dissolves. The solution should look clear and colorless; discard it if it is cloudy or contains visible particles.
7. Label the vial with the reconstitution date and the concentration.
8. Refrigerate immediately at 2 to 8°C. Do not freeze a reconstituted vial.

Drawing and injecting a dose

Units to draw = (prescribed dose in mcg ÷ concentration in mg/mL ÷ 1,000) × 100

Example: a 300 mcg dose at 1 mg/mL concentration. 300 mcg ÷ 1,000 = 0.30 mg. At 1 mg/mL that is 0.30 mL, which is 30 units on a U-100 syringe.

Sermorelin is given subcutaneously, into the fat layer beneath the skin, commonly in the lower abdomen (a couple of inches from the navel) or the outer thigh. General subcutaneous injection principles used for insulin, such as rotating sites to avoid lipohypertrophy, are commonly extrapolated to other subcutaneous peptide injections; ask your prescriber whether they want you to follow a specific rotation schedule rather than assuming one protocol fits all peptides.

Many compounded Sermorelin protocols call for injection roughly 30 to 60 minutes before sleep, timed to the body's largest natural growth hormone pulse during slow-wave sleep. The magnitude and consistency of this effect with Sermorelin specifically should be discussed with your prescriber; do not treat timing as a guarantee of a particular hormonal response.

Storage, stability, and when to discard a vial

Before reconstitution, lyophilized powder is generally stable at room temperature for the duration stated on the compounding pharmacy's label. After reconstitution, compounding pharmacy labels commonly instruct refrigeration at 2 to 8°C and a discard window in the range of 28 to 30 days. Peptide bonds in aqueous solution are inherently less stable than in dry powder form, and degradation accelerates at higher storage temperatures; this is a general principle of peptide chemistry rather than a Sermorelin-specific published figure, and exact potency-loss percentages for compounded Sermorelin vials were not independently verified for this article. Follow the beyond-use date on your specific vial's label rather than a generic number, since beyond-use dating for compounded sterile preparations is set under USP compounding standards administered through the compounding pharmacy.

Discard the vial if you see:

• Cloudiness or particulate matter that does not clear with gentle rolling
• Yellow or brown discoloration
• A period of more than a few hours unrefrigerated
• A date past the beyond-use date on the label
• A stopper punctured well beyond the number of doses the pharmacy anticipated

Common dosing errors

Confusing mg with mcg. Treating 1 mg as 1 mcg produces a 1,000-fold error. Write out units explicitly at every step of a calculation.

Using the wrong syringe. A U-40 syringe delivers a different volume per "unit" mark than a U-100 syringe. Confirm "U-100" is printed on the barrel.

Miscounting the diluent volume. Adding 3 mL of BAC water to a 2 mg vial intended for 1 mg/mL actually yields about 0.67 mg/mL, meaning every dose drawn from the intended table will be roughly a third short of the prescribed amount. Measure carefully and record the actual volume added on the label.

Injecting straight from the refrigerator. Cold solution can sting going in. Letting a filled syringe sit at room temperature for a few minutes before injecting does not meaningfully affect stability over that short period.

What the evidence actually supports, and what it does not

Established: Sermorelin's mechanism (GHRH receptor agonism stimulating endogenous GH release), the historical FDA approval and 2008 market withdrawal of branded Geref, the current status of Sermorelin as a compounded rather than FDA-approved product, and the pharmacy-compounding framework (503A/503B, USP sterile compounding standards) governing how it is prepared.

Plausible but not confirmed by evidence reviewed for this article: specific numeric claims about how much purity a reconstituted Sermorelin solution retains at particular days and temperatures, and the magnitude of body-composition change attributable to Sermorelin specifically over a defined treatment period. Some sources circulating online attach precise percentages or trial results to Sermorelin that, on inspection, describe a different drug or a different population; those numbers were removed here rather than repeated.

Not established: an optimal dose, concentration, or duration that applies uniformly to all adults using compounded Sermorelin off-label, and long-term safety data comparable to what exists for FDA-approved growth hormone therapies.

The Endocrine Society has published a clinical practice guideline on evaluation and treatment of adult growth hormone deficiency that recommends titrating GH-axis therapy to keep IGF-1 within the age- and sex-adjusted normal range. That guideline concerns diagnosed adult GH deficiency treated under medical supervision, and applying its titration philosophy to off-label compounded Sermorelin use is a reasonable clinical extrapolation, not a direct endorsement of Sermorelin itself. Ask your prescriber whether they are using IGF-1 monitoring for this reason, and verify the guideline's current recommendations directly with your prescriber or pharmacist since guideline versions change over time.

Clinician conversation and monitoring framework

This is a discussion and monitoring structure, not a treatment protocol. It is meant to help you organize questions for your prescriber, not to replace individualized dosing decisions, which only your prescriber can make based on your labs, history, and goals.

Two boundaries matter throughout this table. First, nothing in general dosing guidance below substitutes for a lab result or an in-person exam; the numbers in the reconstitution tables above tell you how to measure a prescribed dose accurately, not what dose is right for you. Second, if urgent symptoms appear, such as severe allergic reaction signs (difficulty breathing, throat swelling, widespread hives), that is an emergency care situation, not a "wait for the next checkpoint" situation.

Frequently asked questions

Regulatory status and where to verify it

Branded Sermorelin (Geref) previously held FDA approval and was voluntarily withdrawn from the US market in 2008 for commercial reasons. Sermorelin available today comes from 503A or 503B compounding pharmacies operating under the Federal Food, Drug, and Cosmetic Act and USP sterile compounding standards; it is not an FDA-approved drug product in its current form. Confirm your pharmacy's current 503A or 503B registration status before use, since registration and enforcement actions can change.

References:

• FDA, Registered Outsourcing Facilities (503B): https://www.fda.gov/drugs/human-drug-compounding/registered-outsourcing-facilities
• FDA, Guidance on Sterile Drug Products Produced by Aseptic Processing: https://www.fda.gov/media/71026/download

This article covers general reconstitution mathematics and monitoring framework concepts. It does not provide an individualized dose, and several claims about stability percentages and body-composition outcomes present in earlier drafts of this content could not be verified against a matching primary source and have been narrowed or removed. Confirm all dosing and monitoring decisions with a licensed prescriber familiar with your health history.