IGF-1 LR3 Dosage Guide

Evidence-based protocols for Long Arginine-3 IGF-1 — subcutaneous and intramuscular dosing, hypoglycemia management, strict cycle limits, stacking, and critical safety data.

Compiled by PeptideWiki Editorial Team·Last reviewed February 24, 2026

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Research Peptides

IGF-1 LR3

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What Is IGF-1 LR3?

High-Risk Peptide: IGF-1 LR3 carries significantly greater risks than most research peptides. Life-threatening hypoglycemia, irreversible organ growth, insulin resistance, and tumor promotion are all documented concerns. Every section of this guide includes critical safety information. Read the entire guide before considering use.

IGF-1 LR3 (Long Arginine-3 Insulin-like Growth Factor 1) is a modified analog of human IGF-1, one of the most potent anabolic hormones in the body. It was engineered in the laboratory by making two key modifications to the native IGF-1 molecule: an Arginine substitution at position 3 and a 13-amino-acid N-terminal extension peptide. These changes produce a dramatically more potent and longer-acting compound.

Native IGF-1 is a 70-amino-acid peptide produced primarily by the liver in response to growth hormone (GH) stimulation. In circulation, most IGF-1 is bound to IGF binding proteins (IGFBPs), which limit its biological activity. IGF-1 LR3, at 83 amino acids, has over 100-fold reduced affinity for IGFBPs — meaning far more of the peptide remains free and active. The result is a compound approximately 2–3 times more potent than native IGF-1, with a half-life of 20–30 hours compared to 12–15 hours for the native form.

IGF-1 LR3's primary research interest centers on its ability to promote hyperplasia — the creation of entirely new muscle cells — rather than just hypertrophy (enlarging existing cells). This is a unique capability among anabolic compounds and is the primary reason for its use in research and performance contexts. However, this same growth-promoting potency extends to all tissues, including internal organs and potentially tumors, which is the source of its significant risk profile.

Use our Peptide Dosage to calculate your exact dose based on vial size and concentration.

Dosing information in this guide is derived from research literature and community protocols — not from controlled human clinical trials.

Key Characteristics:

Modified IGF-1 analog — 83 amino acids (vs. 70 for native IGF-1); Arginine substitution at position 3 + 13-amino-acid N-terminal extension
Dramatically reduced IGFBP binding — over 100-fold lower affinity for IGF binding proteins, resulting in far more free active peptide in circulation
2–3x more potent than native IGF-1 — enhanced potency from reduced sequestration by binding proteins combined with structural modifications
Extended half-life — 20–30 hours (vs. 12–15 hours for native IGF-1), enabling once-daily dosing
Promotes hyperplasia — stimulates the creation of new muscle cells (hyperplasia), not just enlargement of existing cells (hypertrophy) — a unique capability among anabolic compounds
Potent glucose-lowering effect — acts on insulin receptors and enhances glucose uptake; hypoglycemia is the primary acute safety concern

For a complete overview of its mechanism and research, see our full IGF-1 LR3 profile. New to peptides? Start with the Beginner's Guide to Peptides.

How IGF-1 LR3 Dosage Is Determined

IGF-1 LR3 dosing — expressed in micrograms (mcg) per injection per day — is derived from in vitro studies, animal models, recombinant IGF-1 clinical research (mecasermin/Increlex), and extensive community experience. No controlled human clinical trials have established an official dosing regimen for IGF-1 LR3 specifically. The commonly used 20–100 mcg range reflects translated research data, clinical analogs, and years of anecdotal reporting.

Research Background

IGF-1 LR3 was originally developed as a research tool for studying IGF-1 receptor signaling in cell culture, where its reduced IGFBP binding made it more reliable than native IGF-1 for experimental purposes. Francis et al. characterized its enhanced potency and reduced binding protein affinity. Tomas et al. demonstrated significant anabolic effects in animal models at microgram-level doses. Clinical data from recombinant human IGF-1 (rhIGF-1, mecasermin) in growth disorders provides additional reference points for dose-response relationships, though rhIGF-1 and IGF-1 LR3 are not pharmacologically equivalent.

Community & Practitioner Experience

The 20–100 mcg daily dosing range has emerged from over a decade of community use. The lower end (20–40 mcg) is favored by beginners assessing tolerance, while the higher end (60–100 mcg) is used by experienced users seeking maximum anabolic effects. Doses above 100 mcg are rarely reported and dramatically increase risk without proportional benefit. The strong consensus on strict 4–6 week cycle limits reflects widespread observation of progressive side effects with extended use.

Strength of evidence: Low. IGF-1 LR3 has no controlled human clinical trials for performance or body composition endpoints. Dosing protocols are derived from animal studies, analogy to recombinant IGF-1 clinical data, and community consensus. The risk profile is well-established from IGF-1 biology research, but optimal dosing for any specific goal is not rigorously validated in humans.

Standard IGF-1 LR3 Dosage Ranges

IGF-1 LR3 is administered once daily by subcutaneous (SC) or intramuscular (IM) injection. Dosing is not split across multiple daily injections due to the long 20–30 hour half-life. The tables below summarize the most commonly used protocols.

Mandatory with every injection: Eat 30–50 grams of fast-acting carbohydrates within 30 minutes of injection. Never inject before sleep, while fasting, or without immediate access to food. Keep glucose tablets or juice on hand at all times.

Dosage by Experience Level

Level	Dose	Frequency	Notes
Beginner	20–40 mcg	Once daily (SC or IM)	Assess tolerance to hypoglycemic effects; maintain for first 3–5 days minimum before increasing
Intermediate	40–60 mcg	Once daily (SC or IM)	Standard effective range for most users; monitor blood glucose weekly
Advanced	60–100 mcg	Once daily (SC or IM)	Maximum recommended range; significantly elevated risk of hypoglycemia and organ growth; strict glucose monitoring required

Subcutaneous vs. Intramuscular Injection

Route	Distribution	Best For	Notes
Subcutaneous (SC)	Systemic	Overall anabolic effect, recovery, body recomposition	Simpler technique; recommended for beginners; inject in abdominal fat or upper thigh
Intramuscular (IM)	Localized + systemic	Targeted muscle growth in specific muscle groups	Inject into freshly trained muscle post-workout; peptide still enters systemic circulation but provides local concentration advantage

Route selection: SC injection is the simplest and most forgiving approach — recommended for beginners and those seeking general systemic effects. IM injection into a freshly trained muscle post-workout is used by advanced users seeking localized hyperplasia in specific muscle groups. Both routes produce systemic effects; IM adds a potential local concentration advantage.

Calculate Your IGF-1 LR3 Dose

IGF-1 LR3 is supplied as a lyophilized (freeze-dried) powder, typically in 1 mg (1,000 mcg) vials. You reconstitute it with bacteriostatic water, then draw your dose using an insulin syringe. The concentration depends on how much water you add to the vial.

Worked Example:

Vial size: 1 mg (1,000 mcg) of IGF-1 LR3
Bacteriostatic water added: 1 mL
Concentration: 1,000 mcg ÷ 1 mL = 1,000 mcg per mL
Target dose: 50 mcg
Volume to draw: 50 ÷ 1,000 = 0.05 mL = 5 units on an insulin syringe

Quick Reference — 1 mg Vial

Bac Water Added	Concentration	50 mcg Dose	Doses per Vial
0.5 mL	2,000 mcg/mL	2.5 units (0.025 mL)	20 doses
1 mL	1,000 mcg/mL	5 units (0.05 mL)	20 doses
2 mL	500 mcg/mL	10 units (0.1 mL)	20 doses

Skip the Math — Use Our

Enter your vial size, water volume, and desired dose — get instant calculations with zero manual math.

IGF-1 LR3 Dosage by Goal

IGF-1 LR3's core mechanism — direct IGF-1 receptor activation driving cell proliferation, protein synthesis, and glucose uptake — supports several goals. The optimal protocol varies by objective, injection route, and risk tolerance.

Reminder: All protocols below require eating 30–50 grams of fast-acting carbohydrates within 30 minutes of every injection. No exceptions.

Systemic Muscle Hypertrophy & Hyperplasia

The most common use case. IGF-1 LR3 promotes both hypertrophy (enlarging existing muscle cells) and hyperplasia (creating new muscle cells). SC injection distributes the peptide systemically for overall muscle growth support.

Dose: 40–80 mcg per day (SC)
Frequency: Once daily, post-workout
Injection site: Abdominal subcutaneous or upper thigh
Duration: 4–6 weeks maximum, then minimum 4 weeks off

Localized Muscle Growth (Site-Specific)

IM injection into a freshly trained muscle immediately post-workout is used to target localized hyperplasia in lagging or prioritized muscle groups. The peptide still enters systemic circulation, but the locally elevated concentration may provide an additional growth stimulus to the injected muscle.

Dose: 40–80 mcg per day (IM)
Frequency: Once daily, immediately post-workout
Injection site: Directly into the muscle group just trained (e.g., deltoid after shoulder training, vastus lateralis after leg training)
Duration: 4–6 weeks maximum, then minimum 4 weeks off

Recovery Support

Lower doses of IGF-1 LR3 support accelerated recovery from intense training through enhanced protein synthesis, satellite cell activation, and improved nutrient partitioning. This approach uses the lower end of the dosing range to minimize side effects while still benefiting from anabolic signaling.

Dose: 20–40 mcg per day (SC)
Frequency: Once daily, post-workout or morning
Injection site: Abdominal subcutaneous
Duration: 4 weeks, then 4 weeks off

Body Recomposition

IGF-1 LR3 enhances nutrient partitioning — directing calories toward muscle tissue and away from fat storage. Combined with a structured training and nutrition program, it supports simultaneous muscle gain and fat loss. SC injection is standard for this application.

Dose: 40–60 mcg per day (SC)
Frequency: Once daily, post-workout
Injection site: Abdominal subcutaneous
Duration: 4–6 weeks maximum, then minimum 4 weeks off

Application note: Regardless of goal, always start at the lower end of the dose range (20–40 mcg) for the first 3–5 days to assess your individual blood glucose response. Increase only after confirming you tolerate the hypoglycemic effects without incident.

IGF-1 LR3 Injection Guide

Post-injection carbohydrate protocol is mandatory. After every injection, eat 30–50 grams of fast-acting carbohydrates (fruit juice, glucose tablets, white bread, rice) within 30 minutes. This is not optional — it prevents life-threatening hypoglycemia.

Subcutaneous (SC) Injection — Step by Step

Wash Hands & Prepare Workspace

Wash hands thoroughly with soap and water. Prepare a clean workspace with your syringe, alcohol swab, reconstituted IGF-1 LR3 vial, and post-injection carbohydrates (have them ready before you inject).

Swab the Vial Stopper

Wipe the rubber stopper of the IGF-1 LR3 vial with an alcohol swab. Let it air-dry for 10–15 seconds.

Draw Your Dose

Pull back the plunger to draw air equal to your dose volume. Insert the needle into the vial, push in the air, invert the vial, and slowly draw out your calculated dose. Tap out any air bubbles.

Choose the Injection Site

For SC injection: the lower abdomen (2–3 inches from the navel) or upper thigh. Rotate injection sites daily to prevent lipodystrophy.

Clean the Injection Site

Swab the chosen injection site with a fresh alcohol pad. Allow to air-dry completely before injecting.

Inject

Pinch a fold of skin between your thumb and forefinger. Insert the needle at a 45-degree angle into the pinched skin fold. Push the plunger slowly and steadily. Withdraw the needle and apply light pressure with the alcohol swab if needed.

Eat Carbohydrates Immediately

Within 30 minutes of injection, consume 30–50 grams of fast-acting carbohydrates. This is mandatory for every injection to prevent hypoglycemia.

Dispose Safely

Place the used syringe immediately into a sharps container. Never recap or reuse needles.

Intramuscular (IM) Injection Notes

For IM injection, use a 25–27 gauge needle, 1 inch in length. Inject at a 90-degree angle directly into the belly of the freshly trained muscle immediately post-workout. Common IM sites include the deltoid, vastus lateralis (outer thigh), and gluteus. Follow the same preparation, cleaning, and post-injection carbohydrate protocol as SC injection.

Reconstitution & Storage

Reconstitution: Add bacteriostatic water to the lyophilized vial by directing the stream down the glass wall — never squirt directly onto the powder cake. Swirl gently, never shake.
Reconstituted storage: Must be refrigerated at 2–8°C; use within 28–30 days
Unreconstituted storage: Refrigerate for maximum shelf life; room temperature is acceptable for short periods
Do not freeze: Freezing reconstituted IGF-1 LR3 can damage the peptide structure through ice crystal formation

For a detailed visual walkthrough, see our Reconstitution Guide.

IGF-1 LR3 Cycle Duration & Timing

Strict cycle limits are non-negotiable. IGF-1 LR3 cycles must not exceed 4–6 weeks. Prolonged use causes irreversible organ growth, progressive insulin resistance, and sustained mitogenic signaling. The minimum off-period is 4 weeks. These limits reflect real physiological consequences, not conservative precaution.

Protocol	On-Cycle	Off-Cycle	Notes
Standard cycle	4 weeks	4 weeks minimum	Recommended for first-time users; assess tolerance and results before considering longer cycles
Extended cycle	5–6 weeks	4–6 weeks minimum	Maximum recommended duration; reserved for experienced users with confirmed glucose tolerance; requires weekly blood glucose monitoring
Conservative cycle	3–4 weeks	4–6 weeks	Shorter on-period with lower doses (20–40 mcg) for recovery-focused use; minimizes risk

Why the Off-Cycle Matters

Insulin sensitivity recovery: IGF-1 LR3 causes progressive insulin resistance with continued use. The off-cycle allows insulin sensitivity to normalize.
Organ growth limitation: Visceral organ hypertrophy (gut distension) is time-dependent. Limiting cycle length limits organ exposure.
IGF-1 receptor desensitization: Prolonged receptor stimulation can lead to downregulation, reducing effectiveness. Time off allows receptor resensitization.
Cancer risk mitigation: Sustained elevated IGF-1 signaling promotes cell division and inhibits apoptosis. Cycling limits the duration of this mitogenic stimulus.

Time of Day

Best timing: Post-workout, with a meal. This aligns the anabolic signal with the post-exercise recovery window and ensures carbohydrate intake to prevent hypoglycemia.
Non-training days: Morning, with breakfast or a carbohydrate-rich meal.
Never before bed: Hypoglycemia during sleep is life-threatening because you cannot recognize or respond to symptoms.
Never while fasting: The glucose-lowering effect of IGF-1 LR3 on an empty stomach dramatically increases hypoglycemia risk.

IGF-1 LR3 Stacking Protocols

IGF-1 LR3 is sometimes combined with other peptides to support upstream growth hormone signaling or to target complementary anabolic pathways. Stacking requires careful attention to timing, as certain combinations carry additive risks.

NEVER combine IGF-1 LR3 with insulin. This combination produces additive hypoglycemia that has been associated with hospitalizations and deaths. Both compounds lower blood glucose through different mechanisms, and the combined effect is unpredictable and potentially fatal. This is an absolute contraindication.

IGF-1 LR3 + Ipamorelin / CJC-1295 (Downstream IGF-1 + Upstream GH Support)

The most common IGF-1 LR3 stack. Ipamorelin and CJC-1295 stimulate natural growth hormone release from the pituitary, which indirectly elevates endogenous IGF-1 production. Combined with direct IGF-1 LR3 administration, this provides both upstream GH support and downstream IGF-1 receptor activation through complementary mechanisms.

Compound	Dose	Timing	Purpose
IGF-1 LR3	40–60 mcg SC or IM	Post-workout (with carbs)	Direct IGF-1 receptor activation, hyperplasia, anabolic signaling
Ipamorelin / CJC-1295	200–300 mcg each SC	Before bed (fasted 2–3 hours)	GH pulse, endogenous IGF-1 elevation, systemic recovery

Timing note: The GH secretagogues are injected before bed on an empty stomach to synergize with the natural nocturnal GH pulse. IGF-1 LR3 is injected post-workout during the day with carbohydrates. This avoids timing conflicts and leverages complementary mechanisms.

IGF-1 LR3 + MK-677 (Direct IGF-1 + Oral GH Secretagogue)

MK-677 (Ibutamoren) is an oral growth hormone secretagogue that provides sustained GH elevation over 24 hours. It offers a non-injectable alternative to Ipamorelin/CJC-1295 for upstream GH support when stacking with IGF-1 LR3.

Compound	Dose	Timing	Purpose
IGF-1 LR3	40–60 mcg SC or IM	Post-workout (with carbs)	Direct IGF-1 receptor activation, hyperplasia
MK-677	10–25 mg oral	Before bed	Sustained GH elevation, appetite increase, recovery

Caution: MK-677 itself can impair glucose tolerance and increase insulin resistance. Combined with IGF-1 LR3, monitor blood glucose closely. This stack carries additive insulin resistance risk.

IGF-1 LR3 + Follistatin 344 (Advanced — Myostatin Inhibition + IGF-1)

An advanced stack combining IGF-1 LR3's anabolic and hyperplastic effects with Follistatin 344's myostatin inhibition. Follistatin binds and neutralizes myostatin, a negative regulator of muscle growth, while IGF-1 LR3 drives direct anabolic signaling. This is considered an aggressive protocol with elevated risk.

Compound	Dose	Timing	Purpose
IGF-1 LR3	40–60 mcg SC or IM	Post-workout (with carbs)	Direct IGF-1 receptor activation, hyperplasia
Follistatin 344	100 mcg SC	Once daily (morning or post-workout)	Myostatin inhibition, removal of muscle growth brake

Advanced users only. This stack carries compounded risks from two potent growth-promoting agents. Limited human data exists for either compound individually, and no data exists for the combination. Strict cycle limits and monitoring are essential.

Explore more combinations with our Peptide Stack Builder or browse the Top 10 Peptide Stacks guide.

Safety, Side Effects & Contraindications

IGF-1 LR3 is a high-risk research peptide. Unlike many peptides with mild side effect profiles, IGF-1 LR3 carries serious, well-documented risks including life-threatening hypoglycemia, irreversible organ growth, progressive insulin resistance, and potential tumor promotion. The risk profile is proportional to the compound's potency.

Hypoglycemia — Primary Acute Danger

IGF-1 LR3 potently lowers blood glucose by activating insulin receptors and enhancing glucose uptake into muscle and other tissues. This is the most immediate and life-threatening risk. Symptoms include:

Mild: Shaking, sweating, hunger, anxiety, rapid heartbeat
Moderate: Confusion, difficulty speaking, blurred vision, weakness, poor coordination
Severe: Seizures, loss of consciousness, coma, death

Mandatory protocol: Eat 30–50 grams of fast-acting carbohydrates within 30 minutes of every injection. Keep glucose tablets or juice on hand at all times. Never inject before sleep or while fasting. If you experience hypoglycemic symptoms, consume fast carbohydrates immediately and reduce your next dose.

Organ Growth (Visceral Hypertrophy)

IGF-1 promotes growth of all tissues, including internal organs. Prolonged or high-dose use can cause growth of the intestines, heart, kidneys, liver, and other abdominal organs. This manifests as progressive abdominal distension (“GH gut” or “palumboism”) and, more critically, as cardiac hypertrophy (enlarged heart). Organ growth from IGF-1 is largely irreversible.

Prevention: Strict adherence to the 4–6 week cycle limit is the primary defense against organ growth. Monitor waist circumference weekly — if it increases despite stable body fat, discontinue immediately.

Insulin Resistance

IGF-1 LR3 competes with insulin for receptor binding and can cause progressive insulin resistance with continued use. This may manifest as elevated fasting blood glucose, increased hunger, and impaired glucose disposal. The effect is generally reversible with adequate off-cycle time but can become persistent with extended or repeated abuse.

Tumor Promotion & Cancer Risk

IGF-1 is a potent mitogen (stimulates cell division) and inhibits apoptosis (programmed cell death) — two key mechanisms relevant to cancer development. Epidemiological studies have consistently linked elevated circulating IGF-1 levels to increased risk of several cancers, including prostate, breast, and colorectal cancer. IGF-1 LR3 is 2–3 times more potent than native IGF-1 and has a longer half-life, amplifying these concerns.

Cancer risk is real, not theoretical. While short-term IGF-1 LR3 use in healthy individuals has not been directly linked to cancer development in controlled studies, the biological mechanism is well-established and the epidemiological evidence for elevated IGF-1 and cancer risk is robust. Anyone with active cancer, a history of cancer, or a strong family history of cancer should not use IGF-1 LR3 under any circumstances.

Other Side Effects

Joint pain or swelling — from fluid retention and tissue growth
Headache — particularly during dose escalation
Lethargy and fatigue — can occur during the first week
Injection site reactions — redness, soreness, minor swelling
Numbness or tingling in extremities — from IGF-1's effects on nerve tissue

Contraindications

Active cancer or history of cancer — IGF-1 is a potent mitogen that promotes cell proliferation and inhibits apoptosis. Absolute contraindication.
Diabetes (Type 1 and Type 2) — the additive blood glucose effects of IGF-1 LR3 on top of existing glucose dysregulation create dangerous and unpredictable hypoglycemia risk.
Cardiac conditions — IGF-1 promotes cardiac hypertrophy. Pre-existing cardiac conditions can be worsened.
Pregnancy and breastfeeding — no safety data exists. Absolute contraindication.
Under 25 years of age — growth plates may not be fully closed. IGF-1 can cause disproportionate bone growth.
Concurrent insulin use — additive hypoglycemia that has been associated with hospitalizations and deaths. Absolute contraindication.
Active organ disease — liver disease, kidney disease, or any condition affecting organs that IGF-1 could cause to enlarge.

Mandatory Monitoring

Blood glucose: Check fasting blood glucose at least weekly with a home glucometer. More frequently during the first week.
Fasting insulin: Check before starting and after completing a cycle to assess insulin resistance impact.
IGF-1 serum levels: Optional but recommended — confirms the peptide is active and helps assess total IGF-1 burden.
Waist measurement: Measure weekly at the same time of day. An increase despite stable body fat may indicate visceral organ growth.
Skin changes: Monitor for new moles, changes in existing moles, or unusual skin growths — IGF-1 promotes cell proliferation.

Regulatory Status: IGF-1 LR3 is not FDA-approved for human use. It is classified as a research peptide. It is prohibited at all times by WADA (World Anti-Doping Agency) for competitive athletes. It is available as a research chemical only. Check local regulations before purchasing.

Common IGF-1 LR3 Dosing Mistakes

IGF-1 LR3 mistakes carry more serious consequences than with most research peptides. Several of these errors can result in medical emergencies:

Not eating carbohydrates after injection: This is the single most dangerous mistake. IGF-1 LR3 potently lowers blood glucose. Failing to eat 30–50 grams of fast-acting carbs within 30 minutes of every injection risks severe hypoglycemia — confusion, seizures, loss of consciousness, and potentially death.

Running cycles longer than 6 weeks: Prolonged IGF-1 LR3 use causes progressive insulin resistance, irreversible organ growth (gut distension), and sustained mitogenic signaling that increases cancer risk. The 4–6 week maximum is not a suggestion — it reflects real physiological limits.

Injecting before bed or while fasting: Hypoglycemia during sleep is life-threatening because you cannot recognize or respond to symptoms. Always inject when you are awake and able to eat immediately. Never inject in a fasted state.

Starting at too high a dose: Beginning at 60–100 mcg without assessing tolerance dramatically increases hypoglycemia risk. Start at 20–40 mcg for the first 3–5 days and increase only after confirming you tolerate the blood glucose effects.

Combining IGF-1 LR3 with insulin: This combination produces additive hypoglycemia that has been associated with hospitalizations and deaths. Both compounds lower blood glucose through different mechanisms, and the combined effect can be catastrophic and unpredictable. Never use these together.

Not monitoring blood glucose: Without glucose monitoring, you have no objective way to assess how IGF-1 LR3 is affecting your blood sugar. Check fasting blood glucose at least weekly. A glucometer is inexpensive and essential during any IGF-1 LR3 cycle.

Using IGF-1 LR3 with a personal or family history of cancer: IGF-1 is a potent mitogen that stimulates cell division and inhibits apoptosis. Elevated IGF-1 levels are epidemiologically linked to increased cancer risk. If you have active cancer, a history of cancer, or a strong family history, IGF-1 LR3 is contraindicated.

Ignoring gut distension or abdominal bloating: Progressive abdominal distension during a cycle is a sign of visceral organ growth — an irreversible effect. If your waist measurement increases despite stable body fat, stop the cycle immediately. Measure your waist weekly.

Shaking the vial during reconstitution: Shaking denatures the peptide by creating foam and shearing the molecular structure. Always swirl gently or roll the vial between your palms until the powder dissolves completely.

Frequently Asked Questions

Key Takeaways

IGF-1 LR3 is a HIGH-RISK research peptide — significantly more dangerous than most peptides. Life-threatening hypoglycemia, irreversible organ growth, and tumor promotion are real concerns, not theoretical.
Standard dose: 20–100 mcg once daily by subcutaneous or intramuscular injection. Start at 20–40 mcg for the first 3–5 days to assess tolerance.
Eat 30–50 grams of fast-acting carbs within 30 minutes of every injection — this is mandatory, not optional.
Never inject before sleep or while fasting — hypoglycemia during sleep can be fatal.
Strict cycle limit: 4–6 weeks maximum, then a minimum of 4 weeks off. Exceeding this risks irreversible organ growth and progressive insulin resistance.
SC injection for systemic effect; IM post-workout for localized growth — both routes are effective.
NEVER combine with insulin — additive hypoglycemia has caused hospitalizations and deaths.
Monitor blood glucose weekly, waist circumference weekly, and fasting insulin before and after each cycle.
Absolute contraindications: cancer (active or history), diabetes, cardiac conditions, pregnancy, under 25, concurrent insulin use.
Not FDA-approved — classified as a research peptide. Prohibited at all times by WADA. Available as a research chemical only.

This article is for educational and informational purposes only. See our Disclaimer.

References

Francis GL, et al. “Insulin-like growth factor 1 and analogs with reduced affinity for IGF-binding proteins: the roles of IGF-binding proteins in biological responsiveness.” Adv Exp Med Biol. 1993;343:113-123.
Tomas FM, et al. “Superior potency of infused IGF-I analogs which bind poorly to IGF-binding proteins is maintained when administered by injection.” J Endocrinol. 1996;150(1):77-84. PubMed
Clark R, et al. “Recombinant human insulin-like growth factor I (IGF-I): risks and benefits of normalizing blood IGF-I concentrations.” Horm Res. 2004;62 Suppl 1:93-100. PubMed
LeRoith D, Roberts CT Jr. “The insulin-like growth factor system and cancer.” Cancer Lett. 2003;195(2):127-137. PubMed
Pollak M. “Insulin and insulin-like growth factor signalling in neoplasia.” Nat Rev Cancer. 2008;8(12):915-928. PubMed
Clemmons DR. “Metabolic actions of insulin-like growth factor-I in normal physiology and diabetes.” Endocrinol Metab Clin North Am.2012;41(2):425-443. PubMed
Rinderknecht E, Humbel RE. “The amino acid sequence of human insulin-like growth factor I and its structural homology with proinsulin.” J Biol Chem. 1978;253(8):2769-2776. PubMed
Laron Z. “Insulin-like growth factor 1 (IGF-1): a growth hormone.” Mol Pathol. 2001;54(5):311-316. PubMed

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