Somatropin 1 pc. x 36 IU – Growth hormone (HGH)

What is Somatropin (HGH 191AA) — 1 pc × 36 IU?

This page concerns Somatropin in the 1 pc × 36 IU format (one vial, ~12 mg). Somatropin (GH 191AA) is recombinant human growth hormone (rhGH) — a protein with a 191-amino-acid chain, identical to the structure of the growth hormone produced naturally by the pituitary gland. The "191AA" designation indicates that the molecule is bioidentical to natural HGH (in contrast to older 192AA forms with an additional methionine). It is the growth hormone itself, not an agent that stimulates its secretion.

This is the key difference from the rest of the category. Secretagogues and GHRH analogs — like Ipamorelin, CJC-1295 or Sermorelin — stimulate the pituitary to release its own GH. Somatropin delivers ready-made growth hormone directly, acting independently of pituitary function. Then, like natural GH, it stimulates the liver to produce IGF-1 — the main mediator of growth and regeneration.

The research-grade Somatropin offered by Peptology is not a medicinal product — it is a lyophilized research hormone intended exclusively for scientific and in vitro applications, not intended for use in humans or animals. It belongs to the category recovery and anabolic peptides.

This version is 1 pc × 36 IU (about 12 mg; conversion ~3 IU = 1 mg). Somatropin is available in three formats: 1 pc × 36 IU, 3 pcs × 36 IU (108 IU in total) and 100 IU (a large package for long protocols). The product is supplied with purity above 99% and independent laboratory analysis (CoA for every batch).

Available formats: 36 IU, 3 × 36 IU and 100 IU

Somatropin is available in three packaging formats. The substance is identical in all of them (recombinant somatropin 191AA, the same purity); only the total amount and unit cost differ.

All three formats contain identical somatropin 191AA with purity > 99% and a laboratory certificate for the batch. The choice depends on the scale of the protocol, not on the quality of the substance.

How Somatropin (1 pc × 36 IU) works — direct growth hormone

In the clinical literature, somatropin is described as a bioidentical growth hormone that acts directly on the GH receptor and triggers the cascade of growth and regeneration. The three effects below together explain its broad metabolic and anabolic action.

Why a "direct hormone" differs from secretagogues

The growth axis works as a cascade: GHRH/GHRP → pituitary → GH → IGF-1. GHRH analogs (CJC-1295, Sermorelin) and GHRP secretagogues (Ipamorelin) act "higher up" — they stimulate the pituitary, and the effect depends on its reserve and preserves natural pulsatility. Somatropin bypasses this stage: it is ready-made GH and acts directly on tissue receptors. This gives a stronger, more direct elevation of GH/IGF-1, but without physiological feedback regulation.

Even "lower" in the cascade is IGF-1 LR3 — the final effector. Somatropin is thus an intermediate link: the GH hormone itself, which only then generates IGF-1. This data comes from the clinical literature and does not constitute a claim about the effect of the research-grade product.

Pharmacokinetics and the IU / mg conversion

Somatropin is a protein with a well-described pharmacokinetic profile. Its relatively short presence in plasma contrasts with the longer, indirect action through IGF-1.

• Structure: recombinant human growth hormone, 191 amino acids (bioidentical to pituitary GH)
• IU / mg conversion: about 3 IU = 1 mg — i.e. 36 IU ≈ 12 mg, and 108 IU (3 × 36) ≈ 36 mg
• Half-life: on the order of 3–4 hours after subcutaneous administration
• Indirect action: effects last longer thanks to IGF-1 induction (with an extended profile)
• Target: the GH receptor (GHR), the JAK2/STAT5 pathway
• Research schedule: in clinical protocols usually daily subcutaneous administration, low daily doses

Comparison: 36 IU vs 3 × 36 IU vs 100 IU

All three formats contain the same, identical somatropin 191AA — they differ only in the total amount and unit cost. The table below helps you choose the package appropriate for the scale of the research protocol.

The choice between formats depends solely on the scale and duration of the research protocol. The substance, purity and batch certificate are identical in all three versions. You will find the larger formats here: 3 pcs × 36 IU and 100 IU.

Clinical and research data on somatropin

Somatropin has one of the best-documented profiles among GH-axis molecules. Below are the most important areas from the literature. The data concern pharmaceutical forms of somatropin.

Safety and pharmacokinetics

In clinical studies, recombinant somatropin 191AA showed good tolerability and a low risk of immunogenicity thanks to its bioidentity with natural GH. The pharmacokinetic profile (short half-life, indirect action through IGF-1) is well characterized.

Growth hormone deficiency and body composition

Somatropin is used clinically in the treatment of growth hormone deficiency (in children and adults) and other indications. In studies it is associated with improved body composition, increased lean mass, reduction of adipose tissue and improved bone mineralization, as well as an increase in IGF-1 concentrations.

Note: The information about clinical studies concerns pharmaceutical forms of somatropin and is presented for scientific and informational purposes. It does not constitute medical advice, a recommendation for use or a claim about the effect of the research-grade product offered by Peptology.

Somatropin 1 pc × 36 IU profile at a glance

• Bioidentical growth hormone (191AA) — the GH itself, not an agent that stimulates the pituitary
• Direct activation of the GH receptor (JAK2/STAT5), independent of pituitary reserve
• Strong IGF-1 induction — the main mediator of growth and regeneration
• Supports lipolysis, lean mass, collagen synthesis and bone mineralization in research models
• Conversion ~3 IU = 1 mg — 36 IU ≈ 12 mg; the 3-pack format = 108 IU ≈ 36 mg

All information provided concerns pharmaceutical forms of somatropin and the clinical literature; it should not be interpreted as a promise of effect, an instruction for use or a claim about the effect of the research-grade product offered by Peptology.

Research dosing protocols

In clinical protocols, somatropin is usually administered subcutaneously, in low daily doses; the IU/mg conversion is helpful:

• Conversion: ~3 IU = 1 mg (36 IU ≈ 12 mg)
• The literature describes low daily doses (e.g. on the order of 2–3 IU/day in anti-aging contexts)
• Route of administration: subcutaneous or intramuscular, per the research protocol
• Monitoring: in studies, the dose is selected based, among other things, on the IGF-1 level

In GH-axis protocols, somatropin is sometimes paired with secretagogues (Ipamorelin, CJC-1295) or with regenerative peptides (BPC-157). These schedules come from the research literature and do not constitute a recommendation for self-administration.

Side effects and safety

The side-effect profile of somatropin is well described in the clinical literature and is mostly dose-dependent. Because it is a direct hormone (stronger than secretagogues), some effects result from excessive activation of the GH/IGF-1 axis.

Most side effects are dose-dependent and reversible after dose adjustment. Because of the direct effect on the GH/IGF-1 axis and glucose, monitoring is important. This information is scientific in nature and does not constitute an instruction for use.

Storage and reconstitution (1 pc × 36 IU)

Somatropin 1 pc × 36 IU is supplied as a lyophilized (freeze-dried) powder in one vial. In lyophilized form it is stable at room temperature, protected from light and moisture — refrigeration before reconstitution is not mandatory. After reconstitution, stability depends on the solvent used, with Peptide Matrix Water™ significantly extending its lifespan.

• Before reconstitution: room temperature, in the original packaging, protected from light and moisture. A refrigerator is not mandatory.
• After reconstitution with Peptide Matrix Water™: stability in the refrigerator +2 °C to +8 °C for up to 60 days under appropriate laboratory conditions — the stabilizing formula extends the lifespan relative to standard solvents.
• After reconstitution with bacteriostatic or sterile water: stability in the refrigerator +2 °C to +8 °C for up to 28 days under appropriate conditions. Do not refreeze the reconstituted solution.
• Reconstitution: in a laboratory setting, Peptide Matrix Water™, bacteriostatic water or sterile water for injection is usually used, depending on the protocol.
• Volume: maximum 3 mL of solvent (capacity of a standard vial). For a precise calculation of the dose in IU/mg, use the peptide calculator.
• Homogenization: add the solvent slowly down the vial wall, without vigorous shaking — protein bonds are sensitive to mechanical stress. Swirl gently, do not shake.

Laboratory tip: With your order, you can add Peptide Matrix Water™ to the cart — a stabilizing solution designed for working with reconstituted research peptides and proteins. More in the article Bacteriostatic water vs acetic acid vs matrix water.

Frequently asked questions — Somatropin 1 pc × 36 IU

What exactly is somatropin (HGH 191AA)?

It is recombinant human growth hormone with a 191-amino-acid chain, bioidentical to the GH produced by the pituitary. It acts directly on the GH receptor and stimulates the production of IGF-1. Unlike secretagogues, it is the hormone itself, not an agent that stimulates its secretion.

How do the 36 IU, 3 × 36 IU and 100 IU formats differ?

The substance is identical in all of them — only the amount and unit cost differ. The 1 pc version is 36 IU (~12 mg) for single or shorter protocols; 3 pcs × 36 IU is 108 IU (~36 mg) in total for longer or parallel protocols; and 100 IU (~33 mg) is the maximum package with the lowest unit cost, for long-term, intensive protocols.

How much is 36 IU in milligrams?

The conversion for somatropin is about 3 IU = 1 mg, so 36 IU is roughly 12 mg. The 3-pack format (108 IU) is about 36 mg in total. For precise calculations, use the peptide calculator.

How does somatropin differ from secretagogues like Ipamorelin?

Secretagogues (Ipamorelin, CJC-1295) stimulate the pituitary to release its own GH, preserving physiological regulation. Somatropin delivers ready-made GH directly — it acts more strongly and independently of the pituitary, but without natural feedback.

Is research-grade somatropin a medicine?

No. The research-grade somatropin offered by Peptology is not a registered drug and is intended exclusively for research purposes, not for use in humans.

How is somatropin stored and reconstituted?

The lyophilized vial is stored at room temperature, protected from light and moisture. After reconstitution, stability depends on the solvent: with Peptide Matrix Water™ — up to 60 days in the refrigerator +2 °C to +8 °C; with bacteriostatic or sterile water — up to 28 days. Avoid refreezing.

Where to buy somatropin for research?

Peptology offers somatropin 191AA (1 pc × 36 IU and 3 pcs × 36 IU) as a research product with confirmed purity above 99% and independent laboratory analysis for every batch. Fast shipping, discreet packaging and certificates of purity. For scientific background, also see the article Peptides — what they are, how they work, main categories and safety profile.

Related products in the Peptology catalog

Researchers working with somatropin often also consider other GH-axis tools — larger packaging, GH secretagogues and the final effector IGF-1. Each of the products below has a certificate of purity above 99%:

See the full catalog: Recovery and anabolic peptides · Solutions for peptides · All peptides · Blog on peptide research

Laboratory reconstitution

Laboratory protocol — reconstitution, research protocols, storage

Standardized protocol applicable to all research peptides in the Peptology catalogue. To calculate the solution concentration (mg/mL) for each vial, use the peptide reconstitution calculator.

60-second protocol

Quick reference

What you need

Five rules for reconstitution

Calculating concentration

Storage

Four mistakes to avoid

Shipping information

🚚 Shipping information

• Products in our warehouse – orders placed by 15:00 on working days are dispatched the same day, later orders on the next working day.

• Delivery with GLS to your address in 3–5 working days.

• Shipping costs €5 and is free from €50.

Frequently Asked Questions (FAQ)

In what form is Somatropin supplied and how should it be stored?

It is supplied as a lyophilized (freeze-dried) powder in a sealed vial. Store the unopened vial dry and protected from light, ideally at 2–8 °C. After laboratory reconstitution, keep the solution at 2–8 °C and use it within the period stated in the “Laboratory reconstitution” tab (up to 60 days with Peptide Matrix Water).

What purity does Somatropin have and how is it tested?

Every batch has a purity of 99% or higher, confirmed by HPLC and mass spectrometry (MS) and documented in a certificate of analysis (CoA). The report for the current batch is shown in the “Laboratory Analysis” tab.

Is a prescription required?

The product is for research use only and does not require a prescription.

Where can I buy Somatropin in Europe and what does it cost?

You can buy Somatropin in Europe online from Peptology, from 57,00 €. Delivery with GLS in 3–5 working days. Shipping is free from 50,00 €. Payment by card. Purity 99%+, with an HPLC report for every batch.

Laboratory Analysis

Somatropin (GH 191AA) - 36 IU - Batch - 0226 - Purity