IGF-1 LR3 Dosage: 20-50mcg/Day Chart + Calculator

IGF-1 LR3 is a modified analog of IGF-1 studied primarily in laboratory and animal models. Barton-Davis et al. (1999) studied native IGF-I gene expression in mouse muscle, not injected LR3 in humans. That mechanism study does not validate a human LR3 regimen; meaningful concerns include hypoglycemia. For a full breakdown of what this peptide does, see our IGF-1 LR3 benefits guide. This is not medical advice.

Research-context information only. IGF-1 LR3 is a research peptide. Protocols, doses, and reactions reported below come from published research and self-reported community sources. This article reports what has been documented, not what should be done. Consult a licensed physician for personal medical decisions.

IGF-1 LR3 Reconstitution and Dose Calculator

This calculator converts a selected vial amount, diluent volume, and entered amount into concentration, mL, and U-100 syringe units. Its initial 1 mg vial + 1 mL example matches the chart below. The values are arithmetic examples, not a validated human dose or a recommendation; the calculation does not establish safety, route, frequency, or solution stability.

Quick Reference: Community-Reported Example

Draw volumes reflect community-documented reconstitution protocols, not a recommended dosing schedule.

For GH secretagogue comparisons, see our MK-677 dosing guide and Ipamorelin dosing guide.

Cycling Details

Community sources describe 10 consecutive days followed by 4 weeks off. The cited animal studies did not test this human schedule, demonstrate that it maximizes muscle growth, or establish that the off-period prevents adverse effects.

Community protocols describe keeping fast-acting carbohydrates available — hypoglycemia is the most immediate risk. Community sources warn against injecting before sleep. Community sources describe starting at 20 mcg for the first 2-3 days, then increasing to 50 mcg; the cited studies do not validate this human titration schedule.

Enhanced Protocol (Community)

Community reports describe some users running longer cycles or higher amounts. The cited studies do not validate these human regimens:

• 4-6 week cycle: 20-50 mcg daily, 4-6 weeks off (less common, higher risk)
• Bilateral IM split: 40-80 mcg/day split between muscle groups post-workout
• Training-day only: 50 mcg on training days (4-5x/week) for 4 weeks

The 10-day on / 4-week off pattern is described in community sources, not established as a safe starting point by the cited studies.

Routes of Administration

Subcutaneous: Abdomen or love handles. Provides systemic IGF-1 LR3 distribution. Consistent absorption, easier injection.

Intramuscular (community reports): Some bodybuilding accounts describe administration near muscles trained that day. The cited native IGF-I gene-transfer study does not demonstrate that injecting LR3 into a chosen muscle produces localized growth in humans.

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Reconstitution Quick Reference

Math: 1,000 mcg / 1 mL = 1,000 mcg/mL. 50 mcg / 1,000 = 0.05 mL = 5 units. Community sources describe gentle mixing, refrigerated storage, and sometimes an acetic-acid diluent. These cited animal studies do not validate a home-preparation method or a 28-day stability claim for either diluent.

For step-by-step reconstitution instructions, see the BPC-157 reconstitution guide — same general technique applies.

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Where These Numbers Come From

IGF-1 LR3 is a research tool and performance compound — it does not have human clinical trial data for the way it's used in the community.

IGF-1 induces muscle hypertrophy through satellite cell activation and increased protein synthesis in differentiated myofibers (Barton-Davis et al., 1999). LR3 IGF-1 infusion in animal models stimulates organ growth (adrenals, gut, kidneys, spleen) while suppressing endogenous IGF-1 and IGFBP levels (Conlon et al., 1995).

Reduced IGF-binding-protein affinity is a property of the LR3 analog, but these animal studies do not establish a human 20-30-hour half-life or a universal 2-3x potency multiplier. The community-reported 20-80 mcg examples are not validated human doses derived from those papers. The cited evidence does not establish a human dose-finding result or a safe schedule.

Stacking Protocols

The following are community-described combinations, not trial-validated regimens.

Community protocols describe running IGF-1 LR3 alone first and lowering LR3 doses to 20-30 mcg when stacking. Community sources emphasize watching blood sugar closely, since multiple compounds may compound hypoglycemia risk, and describe blood work (IGF-1, glucose, insulin, HbA1c) as essential.

Side Effects & Safety

• Hypoglycemia (most immediate risk) — shaking, dizziness, sweating, confusion; community sources describe keeping fast-acting carbs available
• Organ growth — gut distension and cardiomegaly possible with prolonged, high-dose use
• Jaw and hand growth — subtle acromegaly-like changes with chronic use
• Cancer risk — chronically elevated IGF-1 is associated with increased cancer risk in epidemiological studies
• Joint pain — connective tissue changes, water retention
• Fatigue/lethargy — common, especially initially
• Injecting before sleep — community sources warn against this, as hypoglycemia during sleep is dangerous

mg to Units Conversion

On a standard 100-unit insulin syringe, each "unit" equals 0.01 mL (so 100 units = 1 mL). Once IGF-1 LR3 is reconstituted, the conversion from a target dose to syringe units depends on the chosen dilution.

The two reconstitution ratios most often described in community protocols are below.

Reconstitution A: 1 mg vial + 1 mL BAC water (1 mg/mL) — the standard dilution from the Quick Reference above.

Reconstitution B: 1 mg vial + 3 mL BAC water (333 mcg/mL) — more BAC water for larger, easier-to-measure draws.

These conversions reflect the dilutions documented in community reconstitution protocols. They report how the math is described, not a recommended dosing schedule.