Updated March 2026

IGF-1 LR3 Dosing Protocol

Complete IGF-1 LR3 research dosing protocol with community cycle guidance (20-100 mcg/day), reconstitution math, safety context from mecasermin trials, and preclinical evidence references.

Half-life

20-30 hours

Dose range

20-100 mcg/day

Status

Not FDA-approved

Quick Reference Card

Peptide Name

IGF-1 LR3

Aliases

Long Arginine 3-IGF-1, LR3-IGF-1, Long R3 IGF-1

Category / Class

Growth Factor / IGF-1 Analog

Half-Life

20-30 hours

Dosing Frequency

Once daily

Dose Range

20-100 mcg/day (community protocols)

Common Vial Sizes

0.1mg (100mcg), 1mg (1000mcg)

Route of Administration

Subcutaneous (SubQ) or Intramuscular (IM)

Regulatory Status

Not FDA-approved for human use; research compound only. Mecasermin (native rhIGF-1) is FDA-approved for pediatric primary IGFD. Banned by WADA.

Developer

None (research reagent lineage)

Key Stat

Approximately 3x more potent than native IGF-1 with 20-30 hour half-life vs 12-15 hours for native IGF-1 (Tomas et al., 1996).

Peptide Name	IGF-1 LR3
Aliases	Long Arginine 3-IGF-1, LR3-IGF-1, Long R3 IGF-1
Category / Class	Growth Factor / IGF-1 Analog
Half-Life	20-30 hours
Dosing Frequency	Once daily
Dose Range	20-100 mcg/day (community protocols)
Common Vial Sizes	0.1mg (100mcg), 1mg (1000mcg)
Route of Administration	Subcutaneous (SubQ) or Intramuscular (IM)
Regulatory Status	Not FDA-approved for human use; research compound only. Mecasermin (native rhIGF-1) is FDA-approved for pediatric primary IGFD. Banned by WADA.
Developer	None (research reagent lineage)
Key Stat	Approximately 3x more potent than native IGF-1 with 20-30 hour half-life vs 12-15 hours for native IGF-1 (Tomas et al., 1996).

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What Is IGF-1 LR3?

IGF-1 LR3 (Long Arginine 3-IGF-1) is a synthetic analog of human insulin-like growth factor 1 (IGF-1) engineered for enhanced potency and extended biological activity. Also known as Long R3 IGF-1 or LR3-IGF-1, this 83-amino acid peptide retains full agonist activity at the IGF-1 receptor while exhibiting dramatically reduced binding to the six IGF binding proteins (IGFBPs) that normally sequester and inactivate circulating IGF-1.

Structurally, IGF-1 LR3 differs from native IGF-1 (70 amino acids) through two key modifications: the substitution of arginine for glutamic acid at the third position in the amino acid sequence (Arg3), and the addition of a 13-amino acid N-terminal extension peptide derived from methionyl porcine growth hormone (Long). These modifications increase total chain length to 83 amino acids with a molecular weight of approximately 9,117 Da (CAS: 946870-92-4). The reduced IGFBP affinity results in greater free IGF-1 receptor availability and a half-life of approximately 20-30 hours, compared to native IGF-1's 12-15 hours.

IGF-1 LR3 has no formal clinical development program. It was originally developed as a research reagent for in vitro cell culture applications by organizations including CSIRO (Australia) and is manufactured commercially by companies like Repligen under the LONG R3 IGF-I brand for bioprocessing use. It has become widely available through grey market peptide suppliers for research purposes. Native recombinant IGF-1 (mecasermin, brand name Increlex) received FDA approval in 2005 specifically for severe primary IGF-1 deficiency in pediatric patients, providing the most relevant clinical safety data for the IGF-1 pathway. IGF-1 LR3 is prohibited by WADA and all major professional and amateur sporting organizations.

This compound is not FDA-approved for any human therapeutic indication. All information on this page is for educational and research reference purposes only.

How IGF-1 LR3 Works: Direct IGF-1 Receptor Activation & Anabolic Signaling

IGF-1 LR3 acts directly on IGF-1 receptors and drives downstream anabolic and mitogenic signaling through PI3K/Akt/mTOR and MAPK pathway activity.

IGF-1 Receptor (IGF-1R) Activation

IGF-1 LR3 binds directly to IGF-1R, a transmembrane tyrosine kinase receptor expressed across most tissues, including skeletal muscle, bone, liver, kidney, nerve, and connective tissue. Unlike growth hormone, which requires upstream hepatic signaling through JAK2/STAT5, IGF-1 LR3 bypasses that step and initiates intracellular signaling after receptor autophosphorylation.

PI3K/Akt/mTOR Pathway - Protein Synthesis and Cell Survival

IGF-1R activation drives PI3K to Akt to mTOR signaling, which increases muscle protein synthesis, supports glucose and amino acid uptake, reduces protein breakdown, activates satellite-cell repair pathways, and suppresses apoptosis. This pathway is also responsible for insulin-like metabolic activity and hypoglycemia risk.

MAPK/ERK Pathway - Cell Proliferation and Differentiation

IGF-1 LR3 also activates RAS to RAF to MEK to ERK signaling, which supports proliferation and differentiation. This pathway contributes to potential hyperplasia signaling in muscle but also underlies long-term mitogenic concern around sustained receptor stimulation.

Reduced IGFBP Binding - Enhanced Bioavailability

The main pharmacologic advantage over native IGF-1 is reduced binding to IGF binding proteins. With less sequestration, a higher free fraction remains available for receptor engagement. Tomas et al. (1996) reported IGF-1 LR3 was 1.5-2x more potent than equimolar IGF-1 for body weight gain, organ growth, and anti-catabolic effects in rat models.

These receptor and pathway dynamics explain both protocol-level anabolic interest and the main safety liabilities, especially hypoglycemia and potential long-term proliferative risk if exposure is excessive or prolonged.

Tools for this Protocol

peptide reconstitution calculator for reconstitution and units.
dose to units converter to lock in syringe draw volume.

IGF-1 LR3 Dosing Protocol & Cycle Schedule

Assessment

Week 1

20 mcg/day

Once daily, SubQ. Assess tolerance and monitor for hypoglycemia. Administer with food.

Low Dose

Weeks 2-3

20-40 mcg/day

Once daily, SubQ. Most-cited beginner range. Women may remain at 10-20 mcg/day.

Moderate Dose

Weeks 4-6

40-80 mcg/day

Once daily, SubQ. Diminishing returns are commonly reported above 50-60 mcg/day. Monitor glucose regularly.

Off-Cycle

4-6 weeks minimum

0 mcg

Equal time off to reduce receptor desensitization risk. Some protocols also use 5 days on / 2 days off during active cycles.

Phase	Weeks	Weekly Dose	Notes
Assessment	Week 1	20 mcg/day	Once daily, SubQ. Assess tolerance and monitor for hypoglycemia. Administer with food.
Low Dose	Weeks 2-3	20-40 mcg/day	Once daily, SubQ. Most-cited beginner range. Women may remain at 10-20 mcg/day.
Moderate Dose	Weeks 4-6	40-80 mcg/day	Once daily, SubQ. Diminishing returns are commonly reported above 50-60 mcg/day. Monitor glucose regularly.
Off-Cycle	4-6 weeks minimum	0 mcg	Equal time off to reduce receptor desensitization risk. Some protocols also use 5 days on / 2 days off during active cycles.

Important Evidence Disclaimer

No formal human IGF-1 LR3 trials: This dosing guidance is derived from community protocols, extrapolation from mecasermin (Increlex) prescribing data, and preclinical studies. It is not clinical dosing guidance.

Why cycling is critical: Prolonged continuous use may downregulate IGF-1 receptors. Most protocols use 4-6 weeks on, then at least 4-6 weeks off.

Dose-response is not linear: Many sources report that doses above roughly 50-80 mcg/day increase side effects disproportionately compared with incremental benefit.

Timing: Common timing is post-workout on training days and morning with food on rest days. Consume protein and carbohydrates within 15-30 minutes of injection. Do not inject in a fasted state unless clinician-supervised.

Missed dose guidance: Skip the missed dose and continue at the next scheduled time. Do not double dose.

Do not administer before sleep: Exogenous IGF-1 may suppress endogenous GH secretion during sleep. Many protocols keep administration at least 2 hours before bedtime.

IGF-1 LR3 Reconstitution Guide

Vial Size: 1mg (1000mcg)

BAC Water: 1 mL

Concentration: 1000 mcg/mL

20 mcg: 0.02 mL (2 units)

40 mcg: 0.04 mL (4 units)

50 mcg: 0.05 mL (5 units)

80 mcg: 0.08 mL (8 units)

100 mcg: 0.10 mL (10 units)

Vial Size: 1mg (1000mcg)

BAC Water: 2 mL

Concentration: 500 mcg/mL

20 mcg: 0.04 mL (4 units)

40 mcg: 0.08 mL (8 units)

50 mcg: 0.10 mL (10 units)

80 mcg: 0.16 mL (16 units)

100 mcg: 0.20 mL (20 units)

Vial Size: 1mg (1000mcg)

BAC Water: 3 mL

Concentration: 333.3 mcg/mL

20 mcg: 0.06 mL (6 units)

40 mcg: 0.12 mL (12 units)

50 mcg: 0.15 mL (15 units)

80 mcg: 0.24 mL (24 units)

100 mcg: 0.30 mL (30 units)

Vial Size: 0.1mg (100mcg)

BAC Water: 0.5 mL

Concentration: 200 mcg/mL

20 mcg: 0.10 mL (10 units)

40 mcg: 0.20 mL (20 units)

50 mcg: 0.25 mL (25 units)

80 mcg: N/A

100 mcg: N/A

Vial Size: 0.1mg (100mcg)

BAC Water: 1 mL

Concentration: 100 mcg/mL

20 mcg: 0.20 mL (20 units)

40 mcg: 0.40 mL (40 units)

50 mcg: 0.50 mL (50 units)

80 mcg: N/A

100 mcg: N/A

Vial Size	BAC Water Added	Concentration	20 mcg Dose	40 mcg Dose	50 mcg Dose	80 mcg Dose	100 mcg Dose
1mg (1000mcg)	1 mL	1000 mcg/mL	0.02 mL (2 units)	0.04 mL (4 units)	0.05 mL (5 units)	0.08 mL (8 units)	0.10 mL (10 units)
1mg (1000mcg)	2 mL	500 mcg/mL	0.04 mL (4 units)	0.08 mL (8 units)	0.10 mL (10 units)	0.16 mL (16 units)	0.20 mL (20 units)
1mg (1000mcg)	3 mL	333.3 mcg/mL	0.06 mL (6 units)	0.12 mL (12 units)	0.15 mL (15 units)	0.24 mL (24 units)	0.30 mL (30 units)
0.1mg (100mcg)	0.5 mL	200 mcg/mL	0.10 mL (10 units)	0.20 mL (20 units)	0.25 mL (25 units)	N/A	N/A
0.1mg (100mcg)	1 mL	100 mcg/mL	0.20 mL (20 units)	0.40 mL (40 units)	0.50 mL (50 units)	N/A	N/A

Step-by-Step Reconstitution Instructions

Wash hands thoroughly and prepare a clean surface.
Clean peptide and BAC vial stoppers with separate alcohol swabs and let dry.
Draw bacteriostatic water with a sterile mixing syringe (for example, 2 mL for a 1mg vial).
Inject slowly against the inner vial wall, not directly onto the lyophilized powder.
Gently swirl or roll the vial. Never shake.
Wait until the solution is fully clear and particle-free before use.
Store reconstituted solution refrigerated at 2-8C and use within 28-30 days. Do not freeze reconstituted solution.

Need exact syringe units for a custom vial size or water volume? Use the free Peptide Reconstitution Calculator: https://www.peppal.app/calculatorOpen Calculator

IGF-1 LR3 Side Effects - What Research & Clinical Data Show

No formal human clinical trials exist specifically for IGF-1 LR3. The most relevant clinical safety data comes from mecasermin (Increlex), the FDA-approved recombinant native IGF-1, studied in 71 pediatric subjects with primary IGFD treated for a mean duration of 3.9 years (274 subject-years).

Hypoglycemia (most significant risk): In Increlex clinical trials, hypoglycemia was reported in 42% of participants. Symptoms include shakiness, sweating, dizziness, confusion, rapid heartbeat, and blurred vision. Severe episodes can be life-threatening. Always pair administration with carbohydrate and protein intake, and keep fast glucose available.

Water retention and joint effects: Edema and fluid-related effects were common in IGF-1 therapy datasets. Community protocols also report puffiness, mild swelling, and joint stiffness, often dose-dependent and reversible with dose reduction or cycle discontinuation.

Headaches: Headaches are commonly reported early. Increlex safety guidance includes intracranial hypertension monitoring. Persistent or severe headaches, especially with visual symptoms, require medical evaluation.

Injection site reactions: Lipohypertrophy and local irritation can occur. Rotate injection sites consistently.

Organ growth concerns (long-term): Increlex labeling notes rapid increases in renal and splenic length in some patients. Long-term supraphysiologic IGF-1 exposure carries theoretical hypertrophy risk in organ systems.

Cancer risk (theoretical/preclinical): IGF-1 signaling is mitogenic. In 2-year rat carcinogenicity studies with Increlex, increased tumor incidence occurred at high exposure. Elevated IGF-1 is associated with higher risk across some cancer epidemiology datasets. Preclinical IGF-1 LR3 studies have also reported increased tumor growth in tumor-bearing models.

Natural GH suppression: Exogenous IGF-1 may reduce endogenous GH through hypothalamic-pituitary feedback. This supports cycling and timing strategies that avoid sleep-proximal dosing.

Discontinuation rates: In the Increlex program, no subjects withdrew due to adverse reactions, but this does not directly establish comparable risk for unsupervised IGF-1 LR3 protocol contexts.

IGF-1 LR3 Research & Clinical Evidence

Tomas et al. (1996), Journal of Endocrinology

Preclinical (rats) • N/A

Normal growing and dexamethasone-catabolic rats

IGF-1 LR3 was 1.5-2x more potent than native IGF-1 for body weight gain and feed efficiency when continuously infused.

Tomas et al. (1997), Journal of Endocrinology

Preclinical (rats) • N/A

Tumor-bearing catabolic rats

IGF-1 LR3 supported protein turnover but also increased tumor growth in this model.

von der Thusen et al. (2011), American Journal of Pathology

Preclinical (mice) • N/A

Atherosclerosis models

Reported reduced plaque size and lumen stenosis with increased smooth muscle cell content.

MacDonald et al. (published review)

Preclinical • N/A

Intestinal growth models

IGF-1 LR3 enhanced mucosal cellularity more effectively than native IGF-1.

Assefa et al.

Preclinical (cell culture) • N/A

Adipocytes

Demonstrated IGF-1 LR3 effects on glucose uptake in fat cells, supporting metabolic activity findings.

Lu et al.

Preclinical (in vitro) • N/A

Pichia pastoris expression system

Confirmed recombinant IGF-1 LR3 bioactivity with higher proliferation effects than native IGF-1.

Mecasermin (Increlex) Clinical Program

Phase 2/3 (native rhIGF-1) • Mean 3.9 years

71 pediatric patients with primary IGFD

Height velocity improved from 2.8 cm/yr to 8.0 cm/yr in year 1; hypoglycemia reported in 42%.

Borasio et al. (1998), Neurology

RCT (native rhIGF-1) • N/A

ALS patients (European trial)

Placebo-controlled ALS trial did not show significant primary-outcome benefit.

Sorenson et al. (2008), Neurology

RCT (native rhIGF-1) • 2 years

ALS patients

Subcutaneous IGF-1 was not beneficial in this 2-year ALS trial.

Trial	Phase	Duration	Population	Key Result
Tomas et al. (1996), Journal of Endocrinology	Preclinical (rats)	N/A	Normal growing and dexamethasone-catabolic rats	IGF-1 LR3 was 1.5-2x more potent than native IGF-1 for body weight gain and feed efficiency when continuously infused.
Tomas et al. (1997), Journal of Endocrinology	Preclinical (rats)	N/A	Tumor-bearing catabolic rats	IGF-1 LR3 supported protein turnover but also increased tumor growth in this model.
von der Thusen et al. (2011), American Journal of Pathology	Preclinical (mice)	N/A	Atherosclerosis models	Reported reduced plaque size and lumen stenosis with increased smooth muscle cell content.
MacDonald et al. (published review)	Preclinical	N/A	Intestinal growth models	IGF-1 LR3 enhanced mucosal cellularity more effectively than native IGF-1.
Assefa et al.	Preclinical (cell culture)	N/A	Adipocytes	Demonstrated IGF-1 LR3 effects on glucose uptake in fat cells, supporting metabolic activity findings.
Lu et al.	Preclinical (in vitro)	N/A	Pichia pastoris expression system	Confirmed recombinant IGF-1 LR3 bioactivity with higher proliferation effects than native IGF-1.
Mecasermin (Increlex) Clinical Program	Phase 2/3 (native rhIGF-1)	Mean 3.9 years	71 pediatric patients with primary IGFD	Height velocity improved from 2.8 cm/yr to 8.0 cm/yr in year 1; hypoglycemia reported in 42%.
Borasio et al. (1998), Neurology	RCT (native rhIGF-1)	N/A	ALS patients (European trial)	Placebo-controlled ALS trial did not show significant primary-outcome benefit.
Sorenson et al. (2008), Neurology	RCT (native rhIGF-1)	2 years	ALS patients	Subcutaneous IGF-1 was not beneficial in this 2-year ALS trial.

IGF-1 LR3 has broad preclinical use and strong mechanistic plausibility but no dedicated human clinical trial program. Most human safety context comes from native rhIGF-1 (mecasermin), which informs pathway-level risk but cannot be assumed equivalent to IGF-1 LR3 in unsupervised protocol settings. No active ClinicalTrials.gov records were identified for IGF-1 LR3 itself.

Storage & Handling

Lyophilized (powder)

-20C (-4F) freezer

Up to 12 months (long-term)

Lyophilized (powder)

2-8C (36-46F) refrigerator

Several months

Lyophilized (powder)

Room temperature

Weeks (shipping/transit stability)

Reconstituted

2-8C (36-46F) refrigerator

28-30 days

Reconstituted

-20C (frozen aliquots)

Not recommended

State	Temperature	Duration
Lyophilized (powder)	-20C (-4F) freezer	Up to 12 months (long-term)
Lyophilized (powder)	2-8C (36-46F) refrigerator	Several months
Lyophilized (powder)	Room temperature	Weeks (shipping/transit stability)
Reconstituted	2-8C (36-46F) refrigerator	28-30 days
Reconstituted	-20C (frozen aliquots)	Not recommended

Protect from light, avoid freeze-thaw cycles, and inspect for clarity before each draw. Use bacteriostatic water for multi-dose workflows and a fresh sterile syringe for every administration. Some manufacturer data for commercial LONG R3 IGF-I indicates longer controlled stability, but grey-market vial stability may differ.

IGF-1 LR3 vs. IGF-1 DES vs. HGH

Type

IGF-1 LR3: Synthetic IGF-1 analog

IGF-1 DES (1-3): Truncated IGF-1 variant

HGH (Somatropin): Recombinant growth hormone

Amino Acids

IGF-1 LR3: 83

IGF-1 DES (1-3): 67

HGH (Somatropin): 191

Half-Life

IGF-1 LR3: 20-30 hours

IGF-1 DES (1-3): ~20-30 minutes

HGH (Somatropin): 2-3 hours

Receptor Potency

IGF-1 LR3: ~3x native IGF-1

IGF-1 DES (1-3): ~10x native IGF-1

HGH (Somatropin): Indirect (stimulates IGF-1 production)

Action

IGF-1 LR3: Systemic

IGF-1 DES (1-3): Localized and rapid

HGH (Somatropin): Systemic upstream cascade

Dosing Frequency

IGF-1 LR3: Once daily

IGF-1 DES (1-3): 2-3x daily

HGH (Somatropin): 1-2x daily

Common Dose Range

IGF-1 LR3: 20-100 mcg/day

IGF-1 DES (1-3): 50-150 mcg/day (split)

HGH (Somatropin): 2-8 IU/day

Onset of Effects

IGF-1 LR3: Days

IGF-1 DES (1-3): Minutes

HGH (Somatropin): 3-4 weeks

Primary Use Case

IGF-1 LR3: Systemic anabolic support and recomposition

IGF-1 DES (1-3): Targeted hypertrophy at injection-site regions

HGH (Somatropin): Long-term body composition and hormonal support

IGFBP Binding

IGF-1 LR3: Very low

IGF-1 DES (1-3): Very low

HGH (Somatropin): N/A

FDA Status

IGF-1 LR3: Not approved; research compound

IGF-1 DES (1-3): Not approved; research compound

HGH (Somatropin): FDA-approved

WADA Status

IGF-1 LR3: Prohibited

IGF-1 DES (1-3): Prohibited

HGH (Somatropin): Prohibited

Unique Advantage

IGF-1 LR3: Longest-acting IGF-1 variant with once-daily dosing

IGF-1 DES (1-3): Highest receptor potency with localized use

HGH (Somatropin): Broadest endocrine and systemic benefit profile

Feature	IGF-1 LR3	IGF-1 DES (1-3)	HGH (Somatropin)
Type	Synthetic IGF-1 analog	Truncated IGF-1 variant	Recombinant growth hormone
Amino Acids	83	67	191
Half-Life	20-30 hours	~20-30 minutes	2-3 hours
Receptor Potency	~3x native IGF-1	~10x native IGF-1	Indirect (stimulates IGF-1 production)
Action	Systemic	Localized and rapid	Systemic upstream cascade
Dosing Frequency	Once daily	2-3x daily	1-2x daily
Common Dose Range	20-100 mcg/day	50-150 mcg/day (split)	2-8 IU/day
Onset of Effects	Days	Minutes	3-4 weeks
Primary Use Case	Systemic anabolic support and recomposition	Targeted hypertrophy at injection-site regions	Long-term body composition and hormonal support
IGFBP Binding	Very low	Very low	N/A
FDA Status	Not approved; research compound	Not approved; research compound	FDA-approved
WADA Status	Prohibited	Prohibited	Prohibited
Unique Advantage	Longest-acting IGF-1 variant with once-daily dosing	Highest receptor potency with localized use	Broadest endocrine and systemic benefit profile

These compounds target different parts of the GH/IGF-1 axis and are not interchangeable. HGH supports broader endocrine effects, while IGF-1 LR3 and IGF-1 DES focus on direct receptor-level signaling with different duration and distribution profiles.

Reconstitution concentration, injection timing, and cycling strategy differ meaningfully across all three compounds.

IGF-1 LR3 Stacking Protocols

Stack 1

IGF-1 LR3 + GH Secretagogue Stack

Combines direct IGF-1 receptor activation with upstream GH stimulation via CJC-1295 or MK-677. This is a commonly cited growth-focused stack model in community research.

Rationale: upstream GH support plus downstream IGF-1R signaling may produce complementary effects.

See the compound-specific CJC-1295 protocol for additional context.

View CJC-1295 protocol

Stack 2

IGF-1 LR3 + Recovery Stack (BPC-157 / TB-500)

IGF-1 LR3 is often paired with tissue-repair-focused compounds to combine systemic growth signaling with soft-tissue and repair-pathway support.

See the compound-specific BPC-157 protocol for additional context.

View TB-500 protocol

Stack 3

IGF-1 LR3 + Ipamorelin Protocol

Another common GH-axis pairing model combines IGF-1 LR3 receptor-level signaling with ipamorelin-driven endogenous GH pulse support.

See the compound-specific Ipamorelin protocol for additional context.

View Ipamorelin protocol

Frequently Asked Questions - IGF-1 LR3

Q1: What is the starting dose of IGF-1 LR3?

The commonly cited starting dose is 20-40 mcg per day SubQ once daily. Most protocols begin at 20 mcg/day for 5-7 days to assess tolerance before considering gradual increases.

Q2: What is IGF-1 LR3's half-life?

IGF-1 LR3 is generally cited at 20-30 hours, longer than native IGF-1 pathway estimates, primarily due to reduced IGFBP binding and a higher free active fraction.

Q3: What results can be expected from IGF-1 LR3?

Preclinical work suggests stronger anabolic signaling than native IGF-1, with community protocols commonly reporting recomposition and recovery trends. No large-scale human efficacy trials exist specifically for IGF-1 LR3.

Q4: How do you reconstitute IGF-1 LR3?

Inject BAC water slowly against the vial wall, swirl gently, never shake, and refrigerate at 2-8C after mixing. A common setup is 1mg + 2mL BAC water (500 mcg/mL). For custom math use https://www.peppal.app/calculator.

Q5: Is IGF-1 LR3 FDA-approved?

No. IGF-1 LR3 is not FDA-approved for any therapeutic indication and is treated as a research compound. Native mecasermin is FDA-approved only for severe primary IGF-1 deficiency in children.

Q6: What are the most common side effects of IGF-1 LR3?

The main risk is hypoglycemia, with additional reports of edema, headaches, joint discomfort, and injection-site reactions. Long-term concerns include insulin-resistance patterns, organ-growth risk, and theoretical mitogenic cancer risk.

Q7: How does IGF-1 LR3 compare to HGH and IGF-1 DES?

IGF-1 LR3 acts directly on IGF-1 receptors with systemic, longer-duration signaling. IGF-1 DES is shorter-acting and localized, while HGH drives broader upstream hormonal effects that include but are not limited to IGF-1 production.

Q8: What vial sizes are available for IGF-1 LR3?

Most commonly 0.1mg (100mcg) and 1mg (1000mcg) lyophilized vials. Some research suppliers also offer larger quantities for lab applications.

Q9: How much bacteriostatic water should be added to IGF-1 LR3?

For 1mg vials, 2mL is a common practical concentration (500 mcg/mL). 1mL is highly concentrated, while 3mL is more dilute and easier for fine dose measurements.

Q10: What is the maximum dose studied for IGF-1 LR3?

Community protocols often cite up to 100-120 mcg/day, but many sources emphasize diminishing returns and higher adverse-event risk above the 50-80 mcg/day range.

Q11: How should reconstituted IGF-1 LR3 be stored?

Store reconstituted solution refrigerated at 2-8C and use within 28-30 days. Do not freeze reconstituted solution. Protect from light.

Q12: What preclinical research exists for IGF-1 LR3?

Foundational studies from Tomas et al. in the 1990s established higher potency vs native IGF-1 in rat models, with later preclinical work across vascular and metabolic contexts. Human direct-trial data for LR3 remains absent.

Sources & Research

Tomas FM, Lemmey AB, Read LC, Ballard FJ. "Superior potency of infused IGF-I analogues which bind poorly to IGF-binding proteins is maintained when administered by injection." Journal of Endocrinology, 1996 PubMed DOI: 10.1677/joe.0.1500077.
Tomas FM, Knowles SE, Owens PC, et al. "Insulin-like growth factor-I (IGF-I) and especially IGF-I variants are anabolic in dexamethasone-treated rats." Biochemical Journal, 1992 PMC DOI: 10.1042/bj2820091.
Tomas FM, et al. "Effects of insulin and insulin-like growth factors on protein turnover of normal and protein-deficient rats." Journal of Endocrinology, 1997 DOI: 10.1677/joe.0.1550377.
von der Thusen JH, et al. "IGF-1 LR3 effects on atherosclerosis progression." American Journal of Pathology, 2011.
Bailes J, Soloviev M. "Insulin-Like Growth Factor-1 (IGF-1) and Its Monitoring in Medical Diagnostic and in Sports." Biomolecules, 2021 PMC DOI: 10.3390/biom11020217.
Velloso CP. "Regulation of muscle mass by growth hormone and IGF-I." British Journal of Pharmacology, 2008 PMC DOI: 10.1038/bjp.2008.153.
Increlex (mecasermin) Prescribing Information. Ipsen (2019). Label PDF.
Borasio GD, et al. "A placebo-controlled trial of insulin-like growth factor-I in amyotrophic lateral sclerosis." Neurology, 1998 DOI: 10.1212/WNL.51.2.583.
Sorenson EJ, et al. "Subcutaneous IGF-1 is not beneficial in 2-year ALS trial." Neurology, 2008 PMC DOI: 10.1212/01.wnl.0000335970.78664.36.
Mongongu C, et al. "Detection of LongR3-IGF-I, Des(1-3)-IGF-I, and R3-IGF-I using immunopurification and high resolution mass spectrometry for antidoping purposes." Drug Testing and Analysis, 2020 DOI: 10.1002/dta.2792.
Holt RIG, Sonksen PH. "Growth hormone, IGF-I and insulin and their abuse in sport." British Journal of Pharmacology, 2008 PMC DOI: 10.1038/bjp.2008.99.
IGF-1 LR3. Wikipedia. Link.

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Convert this protocol into exact units and save it in Pep Pal with the calculate injection units.

Disclaimer

The information on this page is for educational and research reference purposes only. IGF-1 LR3 is not FDA-approved for any human therapeutic use and is classified as a research compound. No compounds discussed on this site are intended for human consumption. This is not medical advice. Consult a qualified healthcare professional before considering any peptide protocol.

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